APLINDO. Asosiasi Industri Pengecoran Logam Indonesia

BULETIN APLINDO N0.48/2016, April - Mei 2016

APLINDO

Asosiasi Industri Pengecoran Logam Indonesia Gedung Manggala Wanabakti Blok IV Lantai 3 Ruang 303A Jl. Gatot Subroto, Senayan, Jakarta 10270 Telp. 021.573 3832 ; 571 0486; Fax : 021.572 1328

Email : [email protected] Web Site : www.aplindo.web.id

BULETIN - APLINDO No.48/2016

DAFTAR ISI

No.

Uraian

Halaman

1.

Pengantar Redaksi

2

2.

The 24th Annual International Scientile and Technical Conference “Foundry Production and Metallurgy 2016, 19-21 October 2016

4

3.

Izin, Prosedur, Waktu, Dan Biaya Untuk Kemudahan Berusaha Di Indonesia

6

4.

Pusat Logistik Berikat

9

5.

Percepatan Pengembangan Hilirisasi Industri Aluminium

12

6.

Perpres No. 40/2016,Penetapan Harga Gas Bumi

14

7.

Fabrication, magnetostriction properties and applications of Tb-Dy-Fe alloys: a review

15

8.

Effects of Si alloying and T6 treatment on mechanical properties and wear resistance of ZA27 alloys

30

9.

Effects of grain refinement on cast structure and tensile properties of superalloy K4169 at high pouring temperature

41

10.

Data Kendaraan Bermotor 1. Data kendaraan bermotor roda 4 di Indonesia & ASEAN 2. Data kendaraan bermotor roda 2 di Indonesia & ASEAN

47 48

11.

Informasi Umum dan Pameran 1. Website pemerintah yang dapat diakses 2. Website Asosiasi Industri Pengecoran Logam Indonesia 3. Website Himpunan Ahli Pengecoran Logam Indonesia 4. Pameran dan Seminar

51 51 51 51

1


Pengantar Redaksi Pada edisi 48/2016 ini, membahas upaya perbaikan peringkat Ease of Doing Business (EODB) atau kemudahan dalam berusaha, Pemerintah semakin giat melakukan perbaikan baik dari segi peraturan, prosedur perizinan, waktu dan biaya. Peringkat EODB Indonesia, sebagaimana survei Bank Dunia, saat ini berada pada peringkat ke-109 dari 189 negara yang disurvei. Posisi ini tertinggal dibandingkan dengan negara ASEAN lainnya seperti Singapura posisi 1, Malaysia posisi 18, Thailand posisi 49, Brunei Darussalam posisi 84, Vietnam posisi 90 dan Filipina posisi 103. Selain itu juga Pemerintah juga membangun Pusat logistic Berikat dan Kawasan Berikat Kuala Tanjung. Pusat Logistik Berikut dibangun guna mendukung distribusi logistik yang murah dan efisien guna mendukung pertumbuhan industri dalam negeri dan diharapkan Indonesia menjadi Hub Logistik di Asia Pasifik, Sedang Kawasan Kuala Tanjung dibangun untuk mendukung percepatan pengembangan hilirisasi industri berbasis alumunium dan sebagai Hub Barat Toll Laut yang akan dibangun Presiden Jokowi. Dalam edisi ini juga memuat artikel-artikel untuk menambah pengetahuan dibidang pengecoran logam, selanjutnya kami mengharapkan agar buletin ini menjadi media antar anggota maupun antar industri pengecoran didalam negeri dan diluar negeri. Harapan kami, seluruh anggota dapat mengisi buletin ini menjadi kenyataan. Kami informasikan undangan dari Association of foundrymen and metallurgists of the Republic of Belarus yang akan menyelenggarakan The 24th Annual International Scientile and Technical Conference Foundry Production and Metallurgy 2016, 19-21 October 2016 di Binsk, BNTU (Belarus National Technical University) Belarus. Redaksi buletin APLINDO menghimbau anggota APLINDO berpartisipasi dalam mengisi tulisan/artikel, data maupun informasi lain yang berhubungan dengan industri pengecoran logam. Naskah tulisan/artikel dapat dikirim ke sekretariat APLINDO, melalui email ataupun fax.

Redaksi

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IZIN, PROSEDUR, WAKTU UNTUK KEMUDAHAN BERUSAHA DI INDONESIA

Jakarta (28/4/2016) - Presiden Joko Widodo dalam beberapa rapat kabinet terbatas menekankan pentingnya menaikkan peringkat Ease of Doing Business (EODB) atau Kemudahan Berusaha Indonesia hingga ke posisi 40. Untuk itu harus dilakukan sejumlah perbaikan, baik dari aspek peraturan maupun prosedur perizinan dan biaya, agar peringkat kemudahan berusaha di Indonesia terutama bagi UMKM, semakin meningkat. Untuk itu Kementerian Koordinator Bidang Perekonomian membentuk tim khusus untuk melakukan koordinasi dengan Badan Koordinasi Penanaman Modal (BKPM) dan beberapa kementerian dan lembaga terkait guna membuat sejumlah langkah perbaikan. 10 Indikator Tingkat Kemudahan Berusaha Bank Dunia telah menetapkan 10 indikator tingkat kemudahan berusaha yaitu : Memulai Usaha (Starting Business), Perizinan terkait Pendirian Bangunan (Dealing with Construction

Permit), Pembayaran Pajak (Paying Taxes), Akses Perkreditan (Getting Credit), Penegakan Kontrak (Enforcing Contract), Penyambungan Listrik (Getting Electricity), Perdagangan Lintas Negara (Trading Across Borders), Penyelesaian Perkara Kepailitan (Resolving

Insolvency), dan Perlindungan Terhadap Investor Minoritas (Protecting Minority Investors). Indikator ini didasarkan atas survei Bank Dunia pada wilayah Provinsi DKI Jakarta dan Kota Surabaya, Pemerintah menginginkan kebijakan ini bisa berlaku secara nasional. Dari ke-10 indikator itu, Pemerintah akan memangkas proses perizinan dalam upaya perbaikan kemudahan berusaha, antara lain : a. Jumlah prosedur yang sebelumnya berjumlah 94 prosedur, dipangkas menjadi 49 prosedur b. Perizinan yang sebelumnya berjumlah 9 izin, dipotong menjadi 6 izin. c. Waktu yang dibutuhkan total berjumlah 1,566 hari, dipersingkat menjadi 132 hari. Perhitungan total waktu ini belum menghitung jumlah hari dan biaya perkara pada indikator Resolving Insolvency karena belum ada praktik dari peraturan yang baru diterbitkan. Upaya Perbaikan Untuk meningkatkan peringkat kemudahan berusaha ini, sejumlah perbaikan dilakukan pada seluruh indikator yang ada. Pada indikator Memulai Usaha, misalnya, sebelumnya pelaku usaha harus melalui 13 prosedur yang memakan waktu 47 hari Kini hanya akan melalui 7

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BULETIN - APLINDO No.48/2016 prosedur selama 10 hari. Izin yang harus diurus meliputi Surat Izin Usaha Perdagangan (SIUP), Tanda Daftar Perusahaan (TDP), Akta Pendirian, Izin Tempat Usaha, dan Izin Gangguan. Kemudahan lain yang diberikan kepada UMKM adalah : 1.

persyaratan modal dasar pendirian perusahaan. Berdasarkan UU Nomor 40 tahun 2007 tentang Perseroan Terbatas, modal minimal untuk mendirikan PT adalah sebesar Rp 50 Juta. Dengan terbitnya Peraturan Pemerintah Nomor 7 Tahun 2016 tentang Perubahan Modal Dasar Perseroan Terbatas, modal dasar Perseroan Terbatas tetap minimal Rp 50 Juta, tapi untuk UMKM modal dasar ditentukan berdasarkan kesepakatan para pendiri PT yang dituangkan dalam Akta Pendirian PT.

2.

Perizinan Pendirian Bangunan. Kalau sebelumnya harus melewati 17 prosedur yang makan waktu 210 hari untuk mengurus 4 izin (IMB, UKL/UPL, SLF, TDG), kini hanya ada 14 prosedur dalam waktu 52 hari .

3.

Pembayaran pajak yang sebelumnya melalui 54 kali pembayaran, dipangkas hanya menjadi 10 kali pembayaran melalui sistem online. Sedangkan Pendaftaran Properti yang sebelumnya melewati 5 prosedur dalam waktu 25 hari dengan biaya 10,8% dari nilai properti, menjadi 3 prosedur dalam waktu 7 hari dengan biaya 8,3% dari nilai properti/transaksi.

Dalam hal Penegakan Kontrak, untuk penyelesaian gugatan sederhana belum diatur. Begitu pula waktu penyelesaian perkara tidak diatur. Tapi berdasarkan hasil survey EODB, waktu penyelesaian perkara adalah 471 hari. Dengan terbitnya Peraturan Mahkamah Agung Nomor 2 Tahun 2015 tentang Tata Cara Penyelesaian Gugatan Sederhana, maka saat ini untuk kasus gugatan sederhana diselesaikan melalui 8 prosedur dalam waktu 28 hari. Bila ada keberatan terhadap hasil putusan, masih dapat melakukan banding. Namun jumlah prosedurnya bertambah 3 prosedur, sehingga total menjadi 11 prosedur dan waktu penyelesaian banding ini maksimal 10 hari. Penerbitan Peraturan Baru Berkaitan dengan upaya memperbaiki peringkat EODB ini, pemerintah telah menerbitkan 16 peraturan, yaitu: 1. PP No. 7 Tahun 2016 tentang Perubahan Modal Minimum bagi Pendirian PT 2. Permenkumham No. 11/2016 tentang Pedoman Imbalan Jasa Bagi Kurator dan Pengurus 3. Permen PUPR No 5/2016 tentang Izin Mendirikan Bangunan

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BULETIN - APLINDO No.48/2016 4. Permen ATR/BPN no. 8/2016 tentang Peralihan HGB Tertentu di Wilayah Tertentu 5. Permendag No. 14/M-Dag/Per/3/2016 tentang Perubahan Atas Peraturan Menteri Perdagangan No. 77/M-Dag/Per/12/2013 6. Permen ESDM No 8 Tahun 2016 tentang Perubahan atas Peraturan Menteri ESDM No 33/2014 tentang Tingkat Mutu Pelayanan dan Biaya yang Terkait dengan Penyaluran Tenaga Listrik oleh PT PLN 7. Permendag No. 16/M-Dag/Per/3/2016 tentang Perubahan atas Permendag No. 90 Tahun 2014 tentang Penataan dan Pembinaan Gudang 8. Permendagri No 22/2016 tentang Pencabutan Izin Gangguan 9. Peraturan

Dirjen

Pajak

No.

PER-03/PJ/2015

tentang

Penyampaian

Surat

Pemberitahuan Elektronik secara Online 10. SE Menteri PUPR No 10/SE/M/2016 tentang Penerbitan IMB dan SLF untuk Bangunan Gedung UMKM Seluas 1300m2vdengan menggunakan desai prototipe 11. SE Direksi PT PLN No. 0001.E/Dir/2016 tentang Prosedur Percepatan Penyambungan Baru dan Perubahan Daya bagi Pelanggan Tegangan Rendah dengan Daya 100 s.d 200 KVA 12. Perka BPJS No. 1/2016 untuk Pembayaran Online 13. Instruksi Gubernur DKI Jakarta No.42/2016 tentang Percepatan Pencapaian Kemudahan Berusaha 14. SE Mahkamah Agung No2/2016 tentang Peningkatan Efisiensi dan Transparansi Penanganan Perkara Kepailitan dan Penundaan Kewajiban Utang di Pengadilan 15. Keputusan Direksi PDAM DKI Jakarta Tentang Proses Pelayanan Sambungan Air 16. Keputusan Direksi PDAM Kota Surabaya tentang Proses Pelayanan Sambungan Air Peringkat EODB Indonesia, sebagaimana survei Bank Dunia, saat ini berada pada peringkat ke-109 dari 189 negara yang disurvei. Posisi ini tertinggal dibandingkan dengan negara ASEAN lainnya seperti Singapura posisi 1, Malaysia posisi 18, Thailand posisi 49, Brunei Darussalam posisi 84, Vietnam posisi 90 dan Filipina posisi 103. ----0000----

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Pusat Logistik Berikat

Bukan rahasia umum, bahwa biaya logistik di Indonesia merupakan yang termahal di dunia dan salah satu dari permasalahan tersebut adalah banyaknya perizinan untuk mengurus bongkar muat kapal (dwelling time) barang ekspor impor, sehingga Indonesia sulit bersaing dengan negara tetangga. Biaya logistik pelabuhan Indonesia sudah mencapai 27 persen, sementara di negara tetangga, seperti Singapura, Malaysia maupun India atau negara lain berada di angka 15 persen dan di bawah itu. Banyaknya kepentingan instansi kementerian atau lembaga yang mengeluarkan kebijakan masing-masing. Perizinan menjadi biang keladi dari tingginya biaya logistik di pelabuhan. Sebagai contoh : satu barang impor dengan HS Code sekian masuk dalam regulasi larangan terbatas, untuk mengeluarkan barang tersebut membutuhkan waktu pengurusan perizinan sampai dengan satu bulan. Padahal kalau bisa langsung keluar, biaya bisa dipangkas dan penumpukan biaya hanya satu hari. tetapi dengan perizinan sebanyak itu, biaya akan terus membengkak. Indonesia merupakan salah satu negara pengimpor, hampir seluruh barang keperluan industri di Indonesia yang diimpor dari berbagai negara ditimbun di gudang negara tetangga, begitu pula dengan ekspor, banyak komoditas ekspor Indonesia yang menunggu dibeli oleh pembelinya ditimbun di gudang negara tetangga, mengapa Indonesia tidak membuat (pusat logistik berikat) di Indonesia?. Dengan pemikiran tersebut, melalui Peraturan pemerintah (PP) No 85/2015 tentang Tempat Penimbunan Berikat (TPB) Pemerintah telah mengembangkan Pusat Logistik Berikat (PLB) sebagai tempat penimbunan produk atau barang industri dan perdagangan di Indonesia dengan tujuan menjadikan Indonesia sebagai pusat distribusi logistic nasional atau international untuk mendukung distribusi logistic yang murah dan efisien serta mendukung pertumbuhan industri dalam negeri. PLB merupakan suatu kawasan yang digunakan untuk menimbun barang asal luar negeri maupun dari dalam negeri yang pemasukannya diberikan fasilitas kepabeanan, perpajakan, dan fasilitas lainnya. Barang yang dikirim ke PLB ini belum dipungut bea masuk maupun pajak impor, demikian pula dengan pemenuhan ketentuan pembatasan impor belum diberlakukan saat pemasukan barang ke PLB kecuali untuk barang tertentu, sedangkan

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BULETIN - APLINDO No.48/2016 untuk barang asal dalam negeri yang akan diekspor dapat dimasukkan ke PLB dan dapat diselesaikan pemenuhan ketentuan ekspor seperti pembayaran bea keluar dan pemenuhan ketentuan pembatasan ekspor. Jadi PLB merupakan gudang logistik multi fungsi untuk menimbun barang impor atau lokal dengan kemudahan fasilitas perpajakan berupa penundaan pembayaran bea masuk dan tidak dipungut PPN atau PPNBM, serta fleksibilitas operasional. Dengan PLB ini diharapkan dapat mendekatkan jarak antara pelaku usaha dengan bahan baku di dalam negeri sehingga harga bahan baku lebih murah dan dapat menurunkan biaya produksi. Indonesia akan mengembangkan pusat logistik berikat dengan memanfaatkan lahan yang ada. Pemerintah menyerahkan investasi gudang berikat kepada pihak swasta atau perusahaan warehousing, seperti di sektor migas, produsen susu, logam, kapas dan lainnya. Saat ini terdapat 11 perusahaan yang membangun Pusat Logistik Berikat di dekat sentra industri untuk menimbun komoditi yang dibutuhkan industri dalam negeri, seperti kapas, spare part otomotif, peralatan migas, bahan baku industri kecil dan menengah (IKM) dan chemical. Berikut Perusahaan Penerima Fasiltas PLB adalah: Nama Perusahaan

Lokasi

Keterangan

PT Cipta Krida Bahari

Cakung

Supporting Industri Migas & Pertambangan

PT Petrosea Tbk

Balikpapan

Supporting industri Migas & Pertambangan

PT Pelabuhan Panajam (Eastkal-Astra Group)

Balikpapan


PT Dahana (Persero)

Subang


PT Kamadjaja Logistics

Cibitung

Supporting industri Makanan & Minuman

PT Toyota (TMMIN)

Karawang

Supporting Industri Otomotif

PT Agility International

Halim & Pondok Ungu

Supporting industri personal care/home care

PT Gerbang Teknologi Cikarang (Cikarang Dry Port)

Cikarang

Supporting industri tekstil (kapas)

PT Dunia Express

Sunter & Karawang

Supporting industri tekstil (kapas)

PT Khrisna Cargo International

Benoa & Denpasar

Supporting Industri Kecil Menengah

PT Vopak Terminal Merak

Merak

Supporting industri tekstil sintetis

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BULETIN - APLINDO No.48/2016 Perusahaan Penerima Fasiltas PLB yang segera akan menyusul : Nama Perusahaan

Keterangan

Lokasi

Supporting Industri Migas

PT Pertamina Driling Serv.Ind. PT United Tractors

Balikpapan

PT Mexis

Balikpapan

PT Indocafco

Karawang

PT Lautan Luas

Jakarta/Bekasi

PT Linc Logistic

Jakarta/Bekasi

BKDI/PT Tantra Karya Sejahtera

PangkalPinang

PT GMF Aeroasia

Cikarang

PT Damco Indonesia

Marunda

PT Honda Prospect Motor

Karawang

PT Nikawai

Karawang

PT BP Indonesia / CKB

Tangguh

PT Trakindo Utama /CKB

Balikpapan

PT CKB

Balikpapan

PT Megasetia

Jakarta/Bekasi

Supporting industri Migas & Pertambangan Supporting industri Migas & Pertambangan Supporting industri Pemintalan/tekstil Supporting industri Supporting Industri

Bursa Timah- Ekspor

Supporting maintenance Pesawat Ekspor Supporting industri otomotif Supporting industri Pemintalan/tekstil Supporting industri Migas & Pertambangan Supporting industri Migas & Pertambangan Supporting industri Migas & Pertambangan Supporting industri Farmasi

----oooo----

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Percepatan Pengembangan Hilirisasi Industri Aluminium Konsep Kawasan Industri Kuala Tanjung Konsep pengembangan kawasan industri Kuala Tanjung terintegrasi dengan Kawasan INALUM yang mengarah pada percepatan pengembangan hilirisasi industri alumunium yaitu industri turunan dari alumina, industri maritim, industri pengolahan sumber daya alam (komoditi lokal) dan general industri serta sebagai Hub Barat Tol Laut yang akan Presiden Jokowi.

FGD rencana percepatan pengembangan hilirisasi industri alumunium nasional yang dihadiri oleh Dirjen Pengembangan Perwilayahan Industri Kemenperin (Iman Haryono) orang pertama sebelah dari kanan, Dirjen ILMATE Kemenperin (IG Putu Suryawirawan) orang kedua sebelah dari kanan, Deputi bid. Usaha Pertambangan Industri Strategis Kemen BUMN (Fajar Hary Sampurno) orang ketiga sebelah dari kanan, Bupati Batubara (Arya Zulkarnaen) orang keempat sebelah dari kanan, Direktur Utama PT.INALUM (Winardi Suroto) orang kelima sebelah dari kanan.

Masterplan Kawasan Industri Kuala Tanjung Konsep Pengembangan KI Kuala Tanjung terdiri dari 60% fungsi industri dengan rincian: 1. 20 % diperuntukkan untuk industri alumina dan turunannya. 2. 20% diperuntukkan untuk industri maritim, industri perkapalan seperti industri pembangunan kapal baru, bangunan lepas pantai, reparasi kapal, dan ship recycle (penutuhan kapal).

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BULETIN - APLINDO No.48/2016 3. 10 % diperuntukkan untuk industri pengolahan sumber daya alam seperti karet dan kakao. 4. 50 % diperuntukkan untuk general industri seperti Kawasan Berikat (dengan konsep EPTE), industri manufaktur. 5. Dan 40% fungsi Pendukung berupa lahan fasilitas dan infrastruktur.

FGD rencana percepatan pengembangan hilirisasi industri alumunium nasional tanggal 13 April 2016 di Medan Sumatera Utara

Infrastruktur Pendukung Kawasan Industri Kuala Tanjung 

Infrastruktur tersedia berupa jaringan jalan, pengolahan air bersih, listrik, pengolahan limbah, sarana perkantoran, permukiman, sarana rekreasi, dll



Penyediaan Listrik didukung oleh keberadaan PLTA Asahan dengan kapsitas 600MW.



Kebutuhan air bersih diperkirakan sebesar 0,55 liter/ detik/ha. Air bersih bersumber pada pengolahan air bersih (Water Treatment Plant) yang terdapat di dalam kawasan industri



Pengelolaan air limbah menggunakan sistem terpusat yaitu dengan

sistem

pengolahan air limbah (Waste Water Treatment Plant) ----oooo----

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Perpres No. 40/2016 Penetapan Harga Gas Bumi Dengan

pertimbangan

untuk

mendorong

percepatan

pertumbuhan

ekonomi

dan

peningkatan daya saing industri nasional melalui Gas Bumi, serta untuk menjamin efisiensi dan efektivitas pengaliran Gas Bumi, Presiden Joko Widodo pada tanggal 3 Mei 2016, telah menandatangani Peraturan Presiden Nomor 40 Tahun 2016 tentang Penetapan Harga Gas Bumi, dan diposting di website setneg oleh Humas Setneg tanggal 18 Mei 2016. Dalam Perpres itu ditegaskan, harga Gas Bumi

ditetapkan

oleh

Menteri

yang

menyelenggarakan urusan pemerintahan di

bidang

minyak

dan

gas

bumi

(ESDM)sebagai dasar perhitungan bagi hasil pada Kontrak Kerja Sama dan dasar perhitungan penjualan Gas Bumi yang berasal

dari

pelaksanaan

Kontrak

Kerjasama Minyak dan Gas Bumi. Penetapkan harga Gas Bumi sebagaimana dimaksud, dengan mempertimbangkan : a.

Keekonomian lapangan;

b.

Harga Gas Bumi di dalam negeri dan internasional;

c.

Kemampuan daya beli konsumen dalam negeri; dan

d.

Nilai tambah dari pemanfaatan Gas Bumi di dalam negeri,” bunyi Pasal 2 ayat (2) Perpres tersebut.

Dalam hal harga Gas Bumi tidak dapat memenuhi keekonomian industri pengguna Gas Bumi dan harga Gas Bumi lebih tinggi dari 6 dollar AS/MMBTU, Menteri (ESDM, red) dapat menetapkan harga Gas Bumi Tertentu yang diperuntukkan bagi pengguna Gas Bumi yang bergerak di bidang : a. Industri pupuk; b. Industri petrokimia; c. Industri oleochemical; d. Industri baja; e. Industri keramik; f.

Industri kaca;

g. Industri sarung tangan.

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BULETIN - APLINDO No.48/2016 “Perubahan Gas Bumi yang dapat dikenakan Harga Gas Bumi Tertentu ditetapkan oleh Menteri (ESDM, red) setelah berkoordinasi dengan menteri yang menyelenggarakan urusan pemerintahan di bidang perindustrian,” bunyi Pasal 4 ayat (2) Perpres tersebut. Penentuan Harga Gas Bumi Tertentu kepada pengguna Gas Bumi sebagaimana dimaksud dilakukan terhadap Gas Bumi yang dibeli oleh pengguna Gas Bumi: a. Secara langsung dari kontraktor; dan b. Melalui Badan Usaha Pemegang Izin Usaha Niaga Gas Bumi. Tahapan penyelesaian implementasi penetapan harga gas bumi tertentu : 1. Telah diindentifikasikan industri akan mendapatkan insentif penurunan harga gas yang langsung dari hulu dan melalui trader yang telah terindentifikasi secara langsung yaitu industri di Sumatera Utara, PT Pelangi Losarang/Chang Jui Fang, PT Indo Raya Kimia, PT Krakatau Steel, PT Tossa Sakti, PT. Pupuk Kujang, PT Petrokimia Gresik, PT Pusri, PT PIM. 2. Untuk tahap 2 adalah industri yang menerima dari PGN, Pertamina (Niaga) EHK, Sadikun, Rabbana, daftar pengguna dalam proses konfirmasi akhir. 3. Untuk tahap 3, Ditjen Migas akan mengirim surat untuk seluruh Badan Usaha Niaga agar menyampaikan daftar pembeli sektor-sektor penerima insentif penurunan harga gas bumi. Menurut Perpres ini, Kepala SKK Migas melakukan perhitungan penerimaan negara atas penetapan Harga Gas Bumi Tertentu dengan berkoordinasi dengan Menteri ESDM dan menteri yang menyelenggarakan urusan pemerintahan di bidang keuangan negara (Menkeu). “Perhitungan penerimaan negara sebagaimana dimaksud berdasarkan penetapan Harga Gas Bumi Tertentu setelah memperhitungkan besaran penerimaan yang menjadi bagian Kontraktor,” bunyi Pasal 6 ayat (3) Perpres tersebut. Perpres ini juga menegaskan, Menteri ESDM melakukan evaluasi penetapan Harga Gas Bumi Tertentu

setiap

tahun

atau

sewaktu-waktu

dengan

mempertimbangkan

kondisi

perekonomian dalam negeri. Peraturan Presiden ini mulai berlaku pada tanggal diundangkan, dan berlaku surut sejak tanggal 1 Januari 2016,” bunyi Pasal 10 Peraturan Presiden Nomor 40 Tahun 2016, yang telah diundangkan oleh Menteri Hukum dan HAM Yasonna H. Laoly pada tanggal 10 Mei 2016 itu. ----oooo----

16


Fabrication, magnetostriction properties and applications of Tb-Dy-Fe alloys: a review 1

Nai juan Wang , *Yuan Liu

1,2

, Hua-wei Zhang

1,2

, Xiang Chen

1,2

1,2

, and Yan-xiang Li

*) Yuan Liu, Male, born in 1974, Ph.D, Associate Professor. His research mainly focuses on the fabrication and application of porous metals, alloy solidification foundation and process and advanced metallic materials. Email: [email protected]. 1. School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China; 2. Key Laboratory for Advanced Materials Processing Technology (Ministry of Education), Beijing 100084, China Abstract: As an excellent giant-magnetostrictive material, Tb-Dy-Fe alloys (based on Tb0.27-0.30Dy0.730.70Fe1.9-2 Laves compound) can be applied in many engineering fields, such as sonar transducer systems, sensors, and micro-actuators. However, the cost of the rare earth elements Tb and Dy is too high to be widely applied for the materials. Nowadays, there are two different ways to substitute for these alloying elements. One is to partially replace Tb or Dy by cheaper rare earth elements, such as Pr, Nd, Sm and Ho; and the other is to use non-rare earth elements, such as Co, Al, Mn, Si, Ce, B, Be and C, to substitute Fe to form single MgCu 2-type Laves phase and a certain amount of Re-rich phase, which can reduce the brittleness and improve the corrosion resistance of the alloy. This paper systemically introduces the development, the fabrication methods and the corresponding preferred growth directions of Tb-Dy-Fe alloys. In addition, the effects of alloying elements and heat treatment on magnetostrictive and mechanical properties of Tb-Dy-Fe alloys are also reviewed, respectively. Finally, some possible applications of Tb-Dy-Fe alloys are presented. Key words: magnetostriction; Tb-Dy-Fe alloy; fabrication method; applications CLC numbers: TG143.9

Document code: A

Article ID: 1672-6421(2016)02-075-10

1 Introduction The cubic Laves phase RFe2 compounds (R=Sm, Tb and Dy) with cubic MgCu2-type structure have giant room [1-4] temperature magnetostriction constants in excess of 2,000 ppm . However, they also possess huge [5] magnetocrystalline anisotropies , which needs large magnetic field in practical application. Considering that the sign of these magnetocrystalline anisotropy constants differs at room temperature, for example, K 1= 7 -3 7 -3 [6, 7] [8] +2.1×10 erg·cm for DyFe2 and K1= -7.6×10 erg·cm for TbFe2 , Clark et al. suggested that the anisotropy of TbFe2 could be lowered by introducing DyFe2 compound for the anisotropy compensation. On this basis, they tailored the ternary Tb1-x-Dyx-Fe2-y alloy to minimize the anisotropy yet maintaining the large magnetostriction. [9, 10] The optimal compositions occur near 0.7<x<0.73 and 0
-3

which possesses a lower magnetocrystalline anisotropy constant (K 1 = -0.06×10 erg·cm ), while maintaining a [11-14] higher room temperature magnetostriction constant (λ 111=1,500-2,000 ppm) in its single crystal state . This discovery yields a potential future for applications of giant magnetostrictive materials (GMM). In the past four decades, many studies have been conducted during the development of Tb-Dy-Fe alloys with a large magnetostrictive but a small magnetic anisotropy and a low cost. Much work has been focused on increasing the ratio of magnetostriction to magnetocrystalline anisotropy through substituting other rare earth elements for Tb, Dy or transition metal elements for Fe. For example, some researchers proposed to replace Tb [15] [16] [17] [18] [19] [19] [20] [ 21] [22] or Dy by Pr , Nd and Ho , and to substitute Co , Al , Mn , Si , Zr and Ce for Fe, respectively. Beside alloy composition, the magnetostriction of the material can also be controlled by the grain orientation

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BULETIN - APLINDO No.48/2016 which is involved with the different easy magnetization directions (EMD) formed by different fabrication methods [23, 24] [25-29] [30-32] . Bridgman method , floating zone method and Czochralski Method [33-35] were used for preparing a single crystal grain orientation or twins, respectively. Moreover, heat treatment was also employed to [36] [37] improve comprehensive performances of the alloy by Hu Yong et al . and Wei Wu et al. . The fabrication methods for Tb-Dy-Fe alloys and the corresponding preferred growth direction are introduced in this paper. Moreover, effects of some alloying elements and heat treatment on magnetostrictive and mechanical properties of Tb-Dy-Fe alloys are reviewed, respectively. Finally, some possible applications of Tb-Dy-Fe alloys are presented. 2 Fabrication methods [38]

Tb-Dy-Fe alloys with a single crystal or crystal orientation have good magnetostrictive properties . To obtain this kind of crystal, directional solidification technology mainly including Bridgman method, floating zone method and Czochralski method are used for preparing the single crystal grain orientation or twins, respectively. In the following, these three methods will be introduced in detail. 2.1 Bridgman method Bridgman method is named after P. W. Bridgman who is the first one using this method to grow a series of metal [25] single crystals . A typical Bridgman system is shown in Fig. 1(a). The movement of the crucible is controlled by a dropping motor. A longitudinal temperature profile is established at the center of the furnace with a specific temperature gradient near the melting point of the material, as shown in Fig. 1(b). The hole in the lid should be small and the lid should fit well with the furnace body to prevent thermal disturbance. The solidification interface moves up slowly along with the crucible which is cooled from one end to another.

(a)

(b)

Fig. 1: A typical Bridgman system: (a) schematic diagram of furnace; [28] (b) longitudinal temperature profile at furnace center

There can be a seed or no seed for the crystal growth based on the Bridgman method. Given the orientation of seed crystal is <111>, when the movement velocity of induction coil is less than the alloy critical solidification rate, the alloy will grow along with the <111> axis without preferred orientation. However, it is harmful for the magnetostrive property due to the formation of RFe3. When the induction coil movement velocity is faster than the alloy critical solidification rate, it is easy to form dendrites or cellular crystal with easy magnetization direction [26, 27] (EMD) <112> . There is little RFe3 precipitates in this process. But rare earth is easy to burn in this way, and it is difficult to reach a high temperature gradient which has an adverse impact on the solidification structure. In addition, the Bridgman method has limitations and [29] potential issues such as crucible contamination and constraint as well as axial macrosegregation when the [23] pre-alloyed ingots are used .

18


2.2 Floating zone method The floating zone method is to grow crucible contamination-free crystal in such a process that the contamination of the melt and the restriction on the melting temperature of the grown crystal by the crucible material can be [30, 38] avoided . Figure 2(a) exhibits the schematic diagram of floating-zone crystal growth model. The induction coil moves from one end to another, which leads to the melting and solidification of alloys alternately. Dendrites or cellular crystals with easy magnetization direction (EMD) of <112> are prone to form in [31] this way, as shown in Fig. 2(b) . However, this method requires the relative moving speed of the induction coil to be consistent with the heating power, the width of the molten zone, the liquid phase temperature as well as the liquid surface tension, which makes it difficult for practical preparation. At present, the method is mainly used in the fabrication of small-sized specimens. (a)

fig.2 : (a) Schematic diagram of floating-zone crystal growth model [11] (b) Dendritic platelets inTb0.27Dy0.73Fe2

(b)

[30]

;

2.3 Czochralski method [39]

The Czochralski method is a viable one-step route for preparing grain aligned rods of Tb-Dy-Fe alloys schematic diagram of the process is shown in Fig. 3. The

Fig.3 : Schematic diagram of Tb0.3Dy0.7Fe2 produced by Czochralski method

[33]

. The

[38]

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BULETIN - APLINDO No.48/2016 method is mainly composed of fixing a small grain (seed) to the rotatable tungsten rod, then inserting it into the mother alloy melt, thereafter pulling the seed crystal at a certain rate. Based on the seed, melt grows up into a [38] single crystal .

The Czochralski technique is a preferred process in many single crystal growth experiments due to its great [29] controllability over growth rate and the possibility of seeding crystals . However, the overall melting process of raw materials with high temperature gradient which leads to volatility of rare earth elements resulting in composition deviation. Moreover, the slow pulling rate is easy to cause the precipitation of RFe 3 phase and Widmanstatten structure, which can reduce the magnetostrictive properties. The magnetostrictive coefficient is various with different easy magnetization directions, as shown in Fig. 4. The preferred EMD of the single crystal fabricated by this method is <111>.

Fig. 4: Magnetic field dependences of magnetostriction for Tb0.27Dy0.73Fe2 single crystal [24] along the [111], [211] and [011] directions at demagnetized state

From what has been discussed above, it can be found that it is difficult to obtain a bulk single crystal regardless of the methods for magnetostrictive material. Taking the crystal structure into consideration, preparing crystal along with the orientation direction can improve the magnetostriction properties.

3 Effects of substitute elements Comparing with pure nickel and piezoelectric ceramic, Tb-Dy-Fe alloys possess many excellent characteristics such as large coupling coefficient, high energy density, high Curie temperature, large strain and better operation [40] stability, and they have been widely studied and applied to ultrasonic transducer in recent years . However, the high cost of Tb and Dy as well as certain brittleness of Tb-Dy-Fe alloys shortens the operating life-span and limits [41] the large scale production . In addition, the content of Fe element will also affect the characteristics of magnetostrictive materials. The content of RFe3 can be increased with the increasing Fe content, whose magnetostrictive coefficient is quite lower than that of RFe 2, hence resulting in the reduction of the [29] magnetostrictive coefficient . Literatures show that it is feasible to stabilize the Laves phase, reduce brittleness, improve their corrosion resistance, and lower the cost, but without degrading magnetostrictive properties of the alloy by adding some alloying elements. Nowadays, there are two different ways to substitute for alloy elements. One is to partially replace Tb or Dy by cheaper rare earth elements, such as Pr, Nd, Sm and Ho; the other one is to use non-rare earth elements, such as Co, Al, Mn, Si, Ce, B, Be and C, to substitute Fe and form single MgCu 2-type Laves phase and a certain amount of Re-rich phase, which can reduce the brittleness and improve the corrosion resistance of the alloy.

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BULETIN - APLINDO No.48/2016 3.1 Substitute elements for Tb/Dy 3.1.1 Nd NdFe2 has a large theoretical spontaneous magnetostriction (the coefficient of λ111 is up to 2,000 ppm at 0 K). Moreover, the sign of anisotropy constant K1 for NdFe2 is opposite to that of TbFe2 which can reduce the magnetocrystalline anisotropy. Therefore, adding a certain amount of Nd into Tb-Dy-Fe can reduce the [16] magnetocrystalline anisotropy of alloy instead of lowering the magnetostrictive coefficient. J. J. Liu et al studied magnetic properties of Tb0.4-xNdxDy0.6(Fe0.8Co0.2)1.93. Results showed that there are optimal magnetic properties at x=0.05 and 10 KOe for external magnetic field (H). Figure 5 illustrates the magnetic-field and composition dependence of the magnetostriction of Tb0.4-xNdxDy0.6(Fe0.8Co0.2)1.93 alloys. The largest saturation magnetostriction coefficient [42] can be up to 1,170 ppm. In addition, H. Y. Yin et al. found that the Laves phase compound of Tb0.4Dy0.5Nd0.1(Fe0.8Co0.2)1.93 has a large spontaneous magnetostriction, and the coefficient of λ111 is about 1,640 ppm.

3.1.2 Ho Ho has a smaller saturation magnetostriction than that of either Tb or Dy, thus the addition of Ho can reduce the magnetostriction of the alloy. However, the substitution of a small amount of Ho (<20%) for Tb or Dy resulted in a [17, 43] substantial decrease in hysteresis accompanied by only a small loss in magnetostriction . Such a tradeoff is [17] very important for many device applications. M Wun-Fogle et al. researched the magnetization and magnetostriction of dendritic

Fig. 5: (a) Magnetic-field dependence of magnetostrictionλa (=λ||-λ⊥) and (b) composition dependence of magnetostrictionλa of Tb0.4-xNdxDy0.6(Fe0.8Co0.2)1.93 alloys

[16]

[112]

TbxDyyHo1-x-yFe 1.95 rods under compressive stress. Adding Ho into the ternary alloy can clearly reduce the [44] hysteresis, as shown in Fig. 6. Bowen Wang et al. prepared and studied the x(Tb0.15Ho0.85Fe2)+(1x)(Tb0.3Dy0.7Fe2) alloys. It was found that the magnetostriction of alloys decreased with the increase of x. But the ratio (λ///W h) of magnetostriction to hysteresis increases first and exhibits a peak when x=0.1, and then [45] decreases with the increase of Ho content, as shown in Fig. 7. S.C. Busbridge et al. manufactured Tb0.20Dy0.22Ho0.58Fe2 alloy, and tested the magnetostriction coefficient at different temperatures. Results claim that with the temperature decrease, the magnetostriction coefficient of the alloy significantly decreases at low magnetic field, whereas shows a tendency to rise at high magnetic field.This is mainly because the EMD transferred from <111> to <100> with the decrease of temperature.

3.1.3 Pr -6 [46]

Because of high magnetostriction of PrFe2 (close to 5,600×10 ) , it attracts much attention in the research field of magnetostictive materials. At the same time, the magnetocrystalline anisotropy constant of PrFe2 is opposite [47] to TbFe2 , thus the addition of Pr can reduce the magnetocrystalline anisotropy constant of the alloy. Single[48] ion model demonstrates that the ideal radius ratio of Laves phase between rare earth ions and Fe ion is + 1.225. However, the radius of Pr3 is larger than that of the ideal rare earth ions, which deviates much from the [49] ideal radius ratio .

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Fig. 6: Hysteresis width Whvs Ho concentration for samples under applied stresses of -9.8 (filled square), -21.9 (filled triangle), -33.9 (filled diamond), -46.0 (filled circle), -58.1 (open [17] square), and -70.1 MPa (open circle)

Fig. 7: Ratio (λ///Wh) of magnetostriction to hysteresis for x(Tb0.15Ho0.85Fe2)+(1-x)(Tb0.3Dy0.7Fe2) alloys in -1 [44] different compositions at a magnetic field of 320 kA·m

[49]

Therefore, the addition amount of Pr should not exceed 20%, otherwise it is easy to form impurity phase . [15] RenZhi et al. studied the structure and magnetostriction of PrxTb0.2Dy0.8 -xFe1.85C0.05 (x=0.1-0.4) alloys. The research shows that RFe3 phase and rare earth phase appeared when x≥0.2, which leads to the decrease of magnetostriction coefficient and Curie temperature. Figure 8 depicts the magnetostriction coefficient and Curie temperature of the Pr xTb0.2Dy0.8-xFe1.85C0.05 (x=0.10.4) alloy, and it can be seen that Pr0.2Tb0.2Dy0.6Fe1.85C0.05 alloy shows good magnetostrictive properties. Adding B into TbDyPrFe alloys can restrain the formation of RFe3, therefore it can increase the amount of Pr to 30%. W. [50] J. Ren et al. studied the TbxDy0.7-xPr0.3(Fe0.9B0.1)1.93 alloy, and the result showed that Tb0.25Dy0.45Pr0.3 (Fe0.9B0.1)1.93 alloy possesses excellent magnetostrictive properties with λ 111≈1,850 ppm. Moreover, W. J. Ren et [51, 52] al. investigated Tb0.2Dy0.82xPrx(Fe0.9B0.1)1.93 (0<x<0.7) alloys and found that Tb0.2Dy0.4Pr0.4(Fe0.9B0.1)1.93 alloy with the single Laves phase has a large magnetostriction (λ111=1,200 ppm) and a low anisotropy. This alloy may be a good candidate for magnetostriction applications

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(a)

(b)

Fig. 8: Magnetostriction coefficient vs. magnetic field H (a) and Curie temperature vs. x (b) of alloy [15] PrxTb0.2Dy0.8-xFe1.85C0.05 (x=0.1-0.4)

3.2 Substitute elements for Fe 3.2.1 Al /Mn Under low magnetic field, the addition of a small amount of Al can lower the magnetocrystalline anisotropy of the material, but the magnetostrictive coefficient can be decreased with an increase in Al content. Meanwhile, Curie temperature will be reduced. In addition, Al is regarded as an ideal substituent for Fe to increase the resistivity and ductility

[19]

. Manganese is an effective substitution element to improve the magnetostrictive property of the

Tb-Dy-Fe alloys. It is noted that the magnetostriction of Mn-containing compounds is larger than that of Mn-free compounds especially in the lower temperature region. And the addition of Mn can lower the anisotropy energy, and therefore, a low bias field for saturation magnetostriction is expected. This low bias magnetic field is very useful since it is sometimes decisive in the practical application

[19]

.

3.2.2 Co [16]

The addition of a small amount of Co can stabilize the Laves phase , but can reduce the magnetostriction [18] coefficient of materials at the same time . Replacing Fe by a small amount of Co can increase the alloy’s Curie [18] temperature TC, but TC will be deceased with the further increase of Co. Z. J. Guo et al. studied themagnetostrictive properties of (Tb0.7Dy0.3)Pr0.3(Fe1-xCox)1.85, and the results are shown in the Fig. 9 and Fig. 10, respectively. With increasing Co content, the saturation magnetostriction coefficient decreases, but the Curie temperature obtains maximum value at x=0.3. As the Co content continues to increase, the Curie temperature tends to decline. [53]

Z. B. Pan et al. found that the Co element plays an opposite role in the resultant anisotropy as compared with Tb. The smallest anisotropy is obtained for the Tb0.3Dy0.6Nd0.1(Fe 0.8Co 0.2)1.93 compound, which has good magneto-elastic properties, such as the large saturation magnetostrictionλS(~930 ppm) and the high low-field magnetostrictionλa(~670 ppm/3 kOe).

3.2.3 Si Eddy current is formed easily in the process of Tb-Dy-Fe alloy in practical applications, which reduces the efficiency of the transducers. Studies have shown that the eddy current coefficient is inversely proportional to the electrical resistivity for magnetic material

[20]

. Thus, increasing electrical resistivity is a good means

23


Fig. 9: Magnetic field dependence of room temperature magnetostriction λ of annealed [18] polycrystalline (Tb0.7Dy0.3)Pr0.3(Fe1-xCox)1.85 alloys

Fig. 10: Dependence of Curie temperature of (Tb0.7Dy0.3) Pr0.3(Fe1-xCox)1.85 alloys [18] as a function of composition

to reduce the resistivity of the alloy. Some researchers found that adding a certain amount of Si into Tb-Dy-Fe alloy can clearly improve the resistivity

[20]

. Silicon can be randomly dispersed into the alloy to become the

conduction electron scattering center. With the increase of Si content, the number of conduction electrons transferring into the localized 4f orbital of Tb or Dy is increased, but the number of remaining conduction [20] electrons is decreased, which leads to the rise of resistivity. LihongXu et al prepared the Tb0.3Dy0.7(Fe1−xSix)1.95 (x=0,0.025,0.1) alloys with orientation <110>, and studied the magnetostriction coefficient and resistivity along with the change of Si content. Results showed that when x increases to 0.025, the magnetostrictive coefficient drops slightly, but its resistivity increases significantly up to 100 mu Ω cm, as shown in Fig. 11 and Fig. 12, respectively.

Fig. 11: Si content dependence of magnetostriction of<110> oriented [20] Tb0.3Dy0.7(Fe1−xSix)1.95 (x=0, 0.025, 0.1) samples at room temperature

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Fig. 12: Temperature dependence of electrical resistivity of Tb0.3Dy0.7(Fe1−xSix)1.95 [20] (x=0,0.025, 0.1) in the temperature range from 250 to 300 K

In addition, adding small amount of Si into alloy can improve the corrosion resistance. The reason is that the addition of Si improves the natural corrosion potential of the rare earth rich phase, which reduces the electrochemical potential difference between the rare earth rich phase and matrix phase. LihongXu et al. [54] studied the magnetic and corrosion resistance properties of Tb0.3Dy

0.7(Fe1−xSix)1.95

(x=0, 0.025, 0.10) in 3.5% NaCl solution. Figure 13

illustrates the potentiodynamic anodic

Fig. 13: Potentiodynamic anodic polarization curves of Tb0.3Dy0.7(Fe1−xSix)1.95 (x = 0, 0.025 and 0.1) in 3.5wt.% NaCl aqueous solution. SEM surface morphology after corrosion test of Tb0.3Dy0.7 Fe1.95 alloy (a), and

Tb0.3Dy0.7(Fe0.975Si0.025)1.95 alloy (b)

[54]

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BULETIN - APLINDO No.48/2016 polarization curves of Tb0.3Dy 0.7(Fe1-xSi x)1.95 (x=0, 0.025 and 0.1) in 3.5wt.% NaCl aqueous solution, and the SEM surface morphology after corrosion test of Tb0.3Dy0.7Fe1.95 alloy (a), and Tb0.3Dy0.7(Fe0.975Si0.025)1.95 alloy (b). The surface morphology after corrosion test indicates that the corrosion resistance of x=0.025 is better than that of the alloy without Si.

3.2.4 Zr [21]

Li Xiaocheng et al. replaced partial Fe of Tb0.3Dy0.7Fe1.95 alloy by Zr. The addition of different amounts of Zr (x=0, 0.03, 0.06 and 0.09) has varying effects on alloy magnetostrictive properties. The addition of a small amount of Zr can effectively restrain the formation of harmful RFe3 phase, which is good for the improvement of magnetostrictive properties. However, the precipitation of Zr rare earth rich phase is harmful to the magnetostriction enhancement when x=0.09, which has been shown in Fig. 14.

Fig. 14: Magnetostriction and magnetic field strength curves of alloy Tb0.3Dy0.7Fe1.95xZrx

(x=0.03, 0.06, 0.09)

[21]

Fig. 15: Magnetostriction of Tb0.3Dy0.7(CezFe1-z)1.95 as a function of applied field and temperature as z=0.75

[22]

3.2.5 Ce [22]

Colm Mac Mahon et al investigated the magnetization and magnetoelastic properties of melt-spun ribbons of Tb0.3Dy0.7(CezFe1-z)1.95 (0.025≤z≤0.2). The ribbons exhibit a nanocrystalline structure which becomes more -1 amorphous with increasingCe content. Room temperature coercivities remain to be 80 kA·m , but low temperature coercivities increase with the Ce percentage. Saturation magnetostriction varies considerably with the addition of Ce, reaching a maximum of 850 ppm at 230 K, for z= 0.075 composition as shown in Fig. 15.

4 Heat treatment The properties of Tb-Dy-Fe alloys are closely related to the material microstructure. After directional solidification, [38] the Tb-Dy-Fe alloys are usually composed of RFe2 phase and Re-rich phase . The existence of the Re-rich [55] phase can improve the toughness of the alloys . Heat treatment can be used to optimize the morphology of the

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BULETIN - APLINDO No.48/2016 Re-earth phase, reduce defects, and lower inner stress of the alloys, so that the brittleness of material is [56] improved . According to the difference of heat treatment time and procedure, the heat treatment can be divided into one-step treatment and two-step treatment. [36]

Hu Yong et al. prepared <110> oriented Tb0.3Dy0.7Fe2 alloy by the method of zone-melting directional solidification. Results show that the directional solidification Tb-Dy-Fe alloys annealed at 1,203 K for 2 h can achieve optimal performance with saturation magnetostriction of 1,226 ppm and compressive

Fig. 16: Cleaning tool: (a) Photograph; (b) cleaning station with two devices

[66]

strength of 256 MPa. In addition, slow cooling rate can promote high magnetostrictive and mechanical [57] properties. Chengbao Jiang et al have successfully prepared <110> oriented rods of TbDyFemagnetostrictive alloys by zone melting unidirectional solidification. The homogenization annealing for 4 h and 48 h at 1,273 K −3 have been conducted in a quartz cylinder under Ar atmosphere after pumping to 2×10 Pa. A satisfactory −6 magnetostrictive property of 1,970×10 was obtained under 15 MPa pre-stress after heat treatment for 4 h, but there was not further improvement for 48 h annealing. [55]

Wei Wu et al have also prepared <110> oriented rods of TbDyFe giant magnetostrictive alloy using zone melting directional solidification method. Two-step heat treatments were performed at 1,353 K for 2 h, followed by heating at 673, 773, 873, and 973 K for 4 h in Ar atmosphere and air cooling, respectively. Results showed that the alloy can get magnetostriction of 1,324 ppm and compressive strength of 585.16 MPa in a magnetic field -1 of 80 kA·m under 5 MPa pre-stress.

5 Applications The rare earth giant magnetostrictive material (GMM) is an excellent new functional material. Comparing with pure nickel and piezoelectric ceramic, Tb-Dy-Fe alloys possess large coupling coefficient and high Curie [39, 40, 58] temperature as well as higher magnetostriction coefficient , and have attracted much attention for [59-61] applications in high power energy conversion devices . For example, Tb-Dy-Fe alloys can be widely used in [62-67] the design of a large-scale ultrasonic cleaning device for boat cleaning , device for high power ultrasonic [68-74] spot welding (USW), , and device for therapeutic ultrasound (higherpower ultrasound at lower frequencies) [75,76] [77] . Moreover, Tb-Dy-Fe alloys also have a potential future in oil exploitation and pipeline transportation , [87,88] and the recycling of waste energy , such as the emulsification and desulfurization of waste tires . Figure 16 exhibits a large-scale ultrasonic cleaning system, and the schematic picture of a multi-transducer device for boat cleaning (20 kHz). Figure 17 shows the application and the component of the ultrasonic transducer in highpower ultrasonic oil production. Figure 18 shows the state of the pipeline before installation and six months after installation of the Tb-Dy-Fe ultrasonic transducer.

27


Fig. 17: Composition of CSYY60H10 high-power [77] ultrasonic oil production

Fig. 18: State of pipeline (a) before installation and (b) six months after installing Tb-Dy-Fe ultrasonic transducer

6 Conclusion Giant magnetostrictive material (GMM) is a strategic functional material in the 21st century. Recently, this kind of material showed a very broad application prospects in military and civilian dual-use high-tech areas. It has replaced the traditional magnetostrictive materials and has been widely used in advanced technologies, such as magnetomechanical transducers, actuators and adaptive vibration control systems. As an excellent GMM, Tb-DyFe alloy possesses large magnetostriction strain, high energy conversion efficiency, and rapid response rate which have attracted much attention for applications in high power energy conversion devices. However, the cost of the rare earth element Tb and Dy is too high to be widely applied for the materials. Literatures show that it is feasible to enhance magnetostrictive properties of the alloy by adding some alloying elements. Nowadays, there are two different ways to substitute for alloy elements. One is to partially replace Tb or Dy by cheaper rare earth elements, such as Pr, Nd, Sm and Ho; the other one is using non-rare earth elements, such as Co, Al, Mn, Si, Ce, B, Be and C, to substitute Fe to form single MgCu 2-type Laves phase and a certain amount of Re-rich phase, which can reduce the brittleness and improve the corrosion resistance of the alloy. As mentioned above, the properties of the Tb-Dy-Fe alloys play an important role in applications. Therefore, it is critical to develop new RFe2 compound-based giant-magnetostrictive alloys with excellent properties and lower cost.

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BULETIN - APLINDO No.48/2016 [66] Mazue G, Viennet R, Hihn J Y, et al. Large-scale ultrasonic cleaning system: Design of a multi-transducer device for boat cleaning (20 kHz). UltrasonicsSonochemistry, 2011, 18(4): 895-900. [67] Zhimei M. Research Progress in Ultrasonic Scale Inhibition and Elimination. Sino-Global Energy, 2008, 13(4): 92-96. (In Chinese) [68] Bhosale S B, Pawade R S, Brahmankar P K. Effect of process parameters on MRR, TWR and surface topography in ultrasonic machining of alumina–zirconia ceramic composite. Ceramics International, 2014, 40(8): 12831-12836. [69] Liu D F, Cong W L, Pei Z J, et al. A cutting force model for rotary ultrasonic machining of brittle materials. International Journal of Machine Tools and Manufacture, 2012, 52(1): 77-84. [70] Panteli A, Robson J D, Brough I, et al. The effect of high strain rate deformation on intermetallic reaction during ultrasonic welding aluminium to magnesium. Materials Science and Engineering: A, 2012, 556: 31-42. [71] Panteli A, Chen Y C, Strong D, et al. Optimization of aluminium-to-magnesium ultrasonic spot welding. JOM, 2012, 64(3): 414-420. [72] Watanabe T, Sakuyama H, Yanagisawa A. Ultrasonic welding between mild steel sheet and Al-Mg alloy sheet. Journal of Materials Processing Technology, 2009, 209(15): 5475-5480. [73] Matsuoka S, Imai H. Direct welding of different metals used ultrasonic vibration. Journal of Materials ProcessingTechnology, 2009, 209(2): 954-960 [74] Matsuoka S. Ultrasonic welding of ceramics/metals using inserts. Journal of Materials Processing Technology, 1998, 75(1): 259-265. [75] Mason T J. Therapeutic ultrasound an overview. UltrasonicsSonochemistry, 2011, 18(4): 847-852. [76] Inoue K, Nakane Y, Michiura T, et al. Ultrasonic scalpel for gastric cancer surgery: a prospective randomized study. Journal of Gastrointestinal Surgery, 2012, 16(10): 1840-1846. [77] Wang Z, Xu Y, Suman B. Research status and development trend of ultrasonic oil production technique in China. UltrasonicsSonochemistry, 2015, 26: 1-8. [78] Chen T C, Shen Y H, Lee W J, et al. An economic analysis of the continuous ultrasound-assisted oxidative desulfurization process applied to oil recovered from waste tires. Journal of Cleaner Production, 2013, 39: 129-136. [79] Adhikari B, De D, Maiti S. Reclamation and recycling of waste rubber. Progress in Polymer Science, 2000, 25(7): 909-948. [80] Wan M W, Yen T F. Enhance efficiency of tetraoctylammonium fluoride applied to ultrasound-assisted oxidative desulfurization(UAOD) process.Applied Catalysis A: General, 2007, 319: 237-245. [81] Quek A, Balasubramanian R. Liquefaction of waste tires by pyrolysis for oil and chemicals-a review. Journal of Analytical and Applied Pyrolysis, 2013, 101: 1-16. [82] Holst O, Stenberg B, Christiansson M. Biotechnological possibilities for waste tyre-rubber treatment. Biodegradation, 1998, 9(3-4): 301-310. [83] Al-Lal A M, Bolonio D, Llamas A, et al. Desulfurization of pyrolysis fuels obtained from waste: Lube oils, tires and plastics. Fuel, 2015, 150: 208-216. [84] Liu L, Wen J, Yang Y, et al. Ultrasound field distribution and ultrasonic oxidation desulfurization efficiency. UltrasonicsSonochemistry, 2013, 20(2): 696-702. [85] Chen T C, Shen Y H, Lee W J, et al. The study of ultrasound-assisted oxidative desulfurization process applied to the utilization of pyrolysis oil from waste tires. Journal of Cleaner Production, 2010, 18(18): 18501858. [86] Wan M W, Yen T F. Portable continuous ultrasound-assisted oxidative desulfurization unit for marine gas oil. Energy & Fuels, 2008, 22(2): 1130-1135. [87] Yao Xiu-qing, Zhang Jie, Li Fei-fei, et al. Recent Process of Desulfurization Technology of the Clean Fuel. Journal of Liaoning University of Petrol EUM and Chemical Technology, 2004, 24(1): 39-42.1 [88] Dong Chengchun . A brief introduction of ultrasonic desulfurization. Rubber & Plastics Resources Utilization, 2012(3): 27-29. (In Chinese)

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Effects of Si alloying and T6 treatment on mechanical roperties and wear resistance of ZA27 alloys Rui Zhang, Guang-lei Liu, *Nai-chao Si, Yu-yang Peng, Hao Wan, and Ting Liu School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China Abstract: To improve the mechanical properties and wear resistance of ZA27 alloy, Si was introduced to thealloy, and the effect of Si alloying and T6 heat treatment on the microstructure, mechanical properties and wear resistance was investigated. The results show that with 0.55% Si, the microstructure of the alloy can be refined effectively, which leads to the increase of hardness. But the tensile strength and elongation decrease because Si undermines the integrity of the matrix. On the other hand, the dendrites are transformed into a desired α+η+(α+η) mixture with T6 heat treatment, which introduces a remarkable increase to the elongation and hardness of the alloy. The wear resistance of the ZA27 alloy with Si alloying is significantly better than that of the ZA27 alloy without Si. With the increase of Si addition, the wear resistance of the alloy firstly increases and then decreases. In the alloy without Si alloying, severe plastic deformation and large delamination were observed on the worn surface of the alloy. However, with the increase of Si, the main wear mechanism transformed to abrasive wear gradually. In addition, the T6 treatment can further improve the wear resistance of the alloy with Si alloying. Key words: ZA27 alloy; Si alloying; mechanical properties; wear resistance CLC numbers: TG146.21

Document code: A

Article ID: 1672-6421(2016)02-093-08

As-cast zinc-aluminum alloy has been developedfrom late 1930s, which attracted attention of researchers for [1-3] decades as a promising material . The alloy has been widely applied to various fields. One of the most important applications of ZA alloy is as wear parts under low-speed heavy-duty conditions, as a substitute for tin[4-6] bronze due to its better wear resistance, lower cost and longer service life . ZA alloys show advantages in [7] mechanical properties as compared with traditional non-ferrous alloy. The study by Chen T J, et al revealed that ZA alloys have lower friction coefficient and higher bearing capacity than traditional wear resistant materials. The friction coefficient of the ZA27 alloy is even lower than copper alloys through complex modification with RE, [8] Ti, B and Zr . However, composition segregation, poor dimensional and property stability are the main disadvantages, limiting the application of ZA alloy in modern industry. To extend its application area, many optimized processes are used to improve and balance the properties. [9-13]

In recent years, many new effective alloying elements (Cu, Mn, Ti, Re, Si) and alloying methods were discovered, which can improve the mechanical properties and wear resistance of ZA alloys. For example, with 0.4% Ni addition, the microstructures of ZA27 alloys were refined effectively and the wear resistance under high [14] [15] speed heavy - duty conditions was significantly improved . Li Zi-quan and Zhou Heng-zhi investigated the microstructure characteristics of aged SiCp/ZA27 composite, and their study results demonstrated that SiC particulates strongly accelerate neighboring β phase decomposition in the aging process. Stabilizing and solution-aging treatments were typically used in the heat treatment of ZA alloys for refinement, stability and [16] homogenization of the microstructures . Almost all the previous studies were involved in single optimizing process. Very few literatures could be found focusing on composite process for ZA27 alloys. In this paper, Si alloying and T6 heat treatment were used for improving the mechanical properties and wear resistance of the ZA27 alloy. The results will provide a basis for the complex treatment of ZA alloys.

* Nai-chao Si Male, born in 1956, Professor, Ph.D supervisor. His research interests mainly focuse on seismic and vibration damping performance in engineering structure of Cu based shape memory alloys, application of high strength thin walled gray cast irons and austempered ductile irons in automobile engine; and performance optimization of nonferrous alloys.

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BULETIN - APLINDO No.48/2016 1

Experimental procedure

1.1 Alloy preparation The nominal compositions of the ZA27 alloy (in wt.%) are shown in Table 1. Silicon addition in wt.% was 0, 0.3, 0.55 and 0.8, respectively. The alloy was made from commercial purity aluminum (99.80%), zinc (99.99%), magnesium (99.5%), Al-50wt.%Cu master alloy and Al-7wt.%Si master alloy. The aluminum was melted at 700 °C at first, and then the Al-50wt.%Cu and Al-7wt.%Si master alloys were added into the melt. After the master alloys were melted, the zinc was added into the melt. Mechanical mixing for 15 min through a stainless steel stirrer coated with aluminite was applied to ensure homogeneous distribution of the elements in the melt. Then magnesium was pressed into the bottom of the melt to reduce the amount of burning loss. After 5 min, the C2H2Cl6 agent was bubbled into the melt for degassing. Then the melt was refined with 0.2% dewatered ZnCl 2 for 10 min. The overheated melt (600 °C) was cast into a preheated columnar steel mold (200 °C) to obtain alloy samples (Φ35 mm × 270 mm). Wear samples (20 mm × 10 mm × 8 mm) were fabricated using a Wire-Electronic Discharging Machine and tensile samples through machining. One group of the specimens were subjected to heat treatment of solution at 365 °C for 6 h, then quenched in water and artificially aged at 160 °C for 4 h (T6). Table 1: Nominal chemical compositions of ZA27 alloy (wt.%) Al 26-28

Cu 2.0-2.5

Mg

Zn

0.030-0.04

Balance

1.2 Measurement of mechanical properties and microstructural characterization Tensile tests were carried out at room temperature on a 600 kN hydraulic universal testing machine (WE-600) at -1 a 3 mm·min tensile rate. Dimensions of the tensile bar are shown in Fig. 1. Three sets of measured data were used to calculate averages. Bulk hardness of all samples was measured using a Brinell hardness tester with a 5 mm diameter steel ball indenter and under a load of 2.452 kN. The measured impression diameter was used in equation 1 for calculation.

Where F is the load, D is the diameter of steel ball, and d is the indentation

Microstructures of corroded surfaces of the samples were observed under a NIKONPIPHOT300 optical microscope. The corrosives applied consisted of diluted hydrochloric acid (1 vol.%), dilute nitric acid (1 vol.% ), [17] diluted hydrofluoric acid (2 vol.%) and distilled water (96 vol.%) .

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BULETIN - APLINDO No.48/2016 1.3 Sliding wear tests Wear tests were carried out on a block-on-disc friction and wear tester (M-2000). Figure 2 shows the operating principle of the sliding wear process. The wear test cycle lasted 3 h under the load of 600 N with a rotational -1 speed of 200 r·min , and the friction counterpart was made of GCr15. Lubrication was provided by dropping lubricating oil SAE 30 onto the friction surface of the rotating disk at a rate of 15 to 20 drops per min. Wear mass loss was calculated by the difference in sample weight measured before and after the wear test. Coefficients of friction were recorded per min from 30 min after the test start to the end. The coefficient of friction was calculated by equation 2.

where T is time, r the radius of circle, b the width of worn surface, p the load, and θ is equal

2 Results 2.1 Mechanical properties Mechanical properties of the ZA27 alloys with different contents of silicon, and in both as-cast and heat-treated conditions, are shown in Table 2. The increase of Si content caused a slight decrease of the tensile strength and elongation, while their hardness increased with the increase of Si%. A remarkable increase of the elongation and a decrease of the tensile strength were caused by T6 heat treatment. In addition, the hardness of heat treated samples slightly increased compared to that of the as-cast alloy.

2.2

Microstructure

Microstructures of the as-cast alloys are shown in Fig. 3. In the alloy without Si alloying, substantial amounts of large dendritic crystals, developed second dendrite arms and bits of third dendrite arms can be observed (Fig. 3a). However, in the alloy with 0.3% Si, large dendritic crystals decreased and second dendrite arms reduced and shortened, as shown in Fig. 3b. It can be seen in Fig. 3c that, as the content of Si reached 0.55%, almost all the dendrites transformed into equiaxial snowflake grains or blocky crystals. However, coarse dendrites appeared again with 0.8wt.% Si, as shown in Fig. 3d. It reveals that a certain amount of silicon can refine the microstructure of ZA27 alloy. In the process of solidification, the constitutional supercooling formed in the front of solid-liquid interface due to the enrichment of Si, resulted in branches necking and fusing in the process of crystal

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Fig. 3: Microstructure of as-cast alloy with Si content (wt.%): (a) 0, (b) 0.3, (c) 0.55, (d) 0.8

growth. In other words, the growth of α-dendrites was prevented from the enrichment of Si. At the same time, the growth of separated grains was promoted with temperature-fluctuation which benefited the refinement of grains. However, excessive Si would precipitate as primary Si and reduce the content of Si in melt, which weakened the effect of constitutional supercooling and resulted in coarsening of grains. Figures 4a-4c show magnified microstructures of the ZA-27 alloys containing 0.3wt.%, 0.55wt.% and 0.8wt.% Si, respectively, presenting dendritic structure comprising primary α dendrites surrounded by α+η eutectoid phase, residual η phase, ε phase and some black phases in the interdendritic regions. (A- α dendrites core, B- α+η eutectoid structure, C- black phase, D-ε phase). Spectral analysis was carried out on the black phase in Fig. 4c, and the result is shown in Fig. 4d, identifying that the marked zone was primary Si phase. It can also be seen that the morphology of primary Si changed from rod-like to blocky with the increase of Si addition. The microstructure of the ZA27 alloy with 0.55wt.% Si in solution and aging treated condition is shown in Fig. 5. Granular zinc-rich η phases were uniformly distributed in gray matrix structures instead of dendritic structure. After solution treatment at 350 °C, the matrix was β phase. When the specimens were quenched in water (70 °C), part of β phases transformed into (α+η) phase through eutectoid reaction, and a large proportion of β phases retained. When aged at 160 °C, supersaturated η phase precipitated from the residual β phases. The matrix transformed into a α+η mixture. The magnified microstructure in Fig. 5b shows two different mixtures, the lamellar structure produced by eutectoid reaction and the small spherical mixture produced by aging. Through aging heat treatment, η phase was formed by zinc enrichment in local area, and other zinc elements were dispersively distributed in the matrix structure. With the combined effects, the microstructure of fine η phase and α+η mixture was produced by the heat treatment.

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2.3 Wear properties The effect of T6 heat treatment on wear loss of ZA27 alloys with different silicon additions is shown in Fig. 6. It can be noticed that wear loss reached the maximum when silicon content was zero and wear loss of the as-cast alloy with 0.55wt.% Si alloying reached the minimum. Thus, Si alloying appears to do the best optimization for wear resistance of ZA27 alloy when Si was 0.55wt.%. Wear losses of T6 heat-treated alloys decreased drastically. Similarly, wear loss of the heat-treated alloy reached the minimum with 0.55wt.% Si.

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BULETIN - APLINDO No.48/2016 Figure 7 shows worn surfaces of the as-cast ZA27 alloy. Figure 7a is the worn surface of the alloy without Si alloying. Distorted polishing scratches, sags and crests can be found on the surface which may be caused by friction heat. In Fig. 7b (0.3wt.% Si), large-scale of delamination was observed on the worn surface, which could be attributed to adhesive wear mechanism. Continuous scratches appeared on the surface when Si% increased up to 0.55wt.%, which was caused by abrasive wear mechanism (Fig. 7c). Although adhesive wear still existed, the extent was greatly reduced, and the worn surface became relatively smooth. Abrasive wear became the main wear mechanism. When Si addition increased to 0.8wt.%, adhesive

Fig. 7: Wear appearances of as-cast alloys with Si addition (wt.%): (a) 0, (b) 0.3, (c) 0.55, (d) 0.8

wear became aggravated (Fig. 7d), because blocky or rod-shaped primary Si phases had undermined the integrity of the matrix alloy. In this case, Si phase can be separated by friction force along the direction perpendicular to the force. Stress concentrations arising in these small gaps led to the formation of cracks and delamination. Worn surfaces of the T6 heat-treated alloys are shown in Fig. 8. The worn surface of the alloy without Si alloying is displayed in Fig. 8a. Slight adhesive wear occurred on the worn surface. Delamination still existed on the worn surface of the alloy without Si alloying, but the thickness and size decreased significantly. Abrasive wear mechanism became the main wear mechanism of the alloy with 0.3% Si (Fig. 8b). But polishing scratches were still thick and broad. As the Si% increased to 0.55% (Fig. 8c), abrasive wear became the predominant wear mechanism and the worn surface tended to be smooth and clean with fine polishing scratches. When the Si addition reached 0.8wt.% (Fig. 8d), abundant blocky Si phase formed, which could easily split away from the matrix. The blocky Si phase could serve as wear debris to cut the matrix, leading to relatively thick scratches again.

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Fig. 8: Worn surfaces of heat-treated alloys with Si addition (wt.%): (a) 0, (b) 0.3, (c) 0.55, (d) 0.8

3

Discussion

The effects of Si alloying on mechanical properties of the ZA27 alloys are shown in Table 2. The results indicate that the addition of Si reduced the tensile strength, while increased the hardness. Si alloying refined the microstructure of the alloy (Fig. 3), but at the same time, primary Si phases undermined the integrity of the matrix alloy (Fig. 4a, 4b, 4c). The morphologies of primary Si phases are usually rod-shaped and blocky. The smallangle gap in the matrix alloy formed by sharp ends of Si phase easily produces stress concentration, leading to the decrease of the tensile strength and elongation. But the hardness should not be impacted by this effect. On the contrary, the hardness of the alloy increased due to the high hardness silicon crystal and the refined microstructure. Through the T6 heat treatment, the tensile strength decreased, but the elongation increased significantly (Table [18] 2). This result is in line with Babic Miroslav’s research . A new α + η + (α+η) microstructure was reformed by the heat treatment. Deformation on the mixture was more uniform, which increased the elongation. The soft η phase was dispersively distributed on the matrix, decreasing the difficulty of deformation, which led to the decrease of deformation force. The friction coefficient of the as-cast ZA27 alloys during the sliding wear test is shown in Fig. 9. Since the initial 30 min was the running-in period, records of friction coefficients started from 30-min mark. From the diagram, it can be clearly noticed that high friction coefficient and drastic fluctuation occurred in the curve of the ZA27 alloy without Si alloying (Curve-A) because of adhesive wear. With the increase in Si content, the average friction coefficient decreased significantly (Curve-B, Curve-C). But when Si content reached 0.8wt.%%, friction coefficient of the alloy (Curve-D) increased to 0.04 on average, and fluctuation of the friction coefficient increased. This is in accordance with Fig. 7. In Fig. 6, the T6 heat-treated ZA27 alloy with 0.55wt.% Si shows the best wear resistance. Silicon particles and ε(CuZn4) phases acted as supporting load and limited the direct contact between Zn-Al matrix and the steel slider. At the microcosmic level, soft matrix phases were first worn off, and hard spots highlighted on the wear

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BULETIN - APLINDO No.48/2016 contact surface and acted as the supporting load, avoiding abrasions of the soft matrix. At the same time, the worn parts played a good storage function in the

Fig. 9: Friction coefficient of as-cast alloys

condition of oil lubrication. The ε(CuZn4) phase showed the feature of high hardness, but due to its small proportion in the matrix, it cannot support the heavy load perfectly, and may even have the opposite effect. Namely, the ε(CuZn4) phase may be forced to cut into the matrix. The situation happened in the wear process of the ZA27 alloy without Si alloying. The temperature on surface of the alloy increased rapidly due to the direct contact between the matrix and the steel slider, resulting in the softening effect of the surface layers. Adhesive wear mechanism became an important wear mechanism, leading to the drastic fluctuation of friction coefficient. When excessive Si was added, primary rod-shaped Si phases changed to blocky particles. The blocky Si particles could easily split away from the matrix, and then became abrasive particles to cut the alloy matrix. Thus the wear property deteriorated when Si increased to 0.8wt.%. The characteristics of the friction coefficient of T6 heat-treated ZA-27 alloys during sliding are illustrated in Fig. 10. The monolithic friction coefficient and the fluctuation decreased enormously compared with the as-cast alloy. The friction coefficient of the heat treated alloy without Si alloying was about 0.042. It reached the minimum (about 0.015) when Si content was 0.55%, while with further increase of Si addition, the friction coefficient increased again. It can be seen that the reduction in friction coefficient occurred in the rear part of curves C and D, which may be caused by surface hardening. T6 heat treatment transformed the microstructure into a fine mixture. Under the condition of oil lubrication, small spherical η phases were worn away first, then the pits in reserve were filled with lubricated oil. This structure improved the wear resistance of the alloy.

Figure 11 shows the deformation on the edge of the alloy specimen without Si alloying. The lamellar structure was caused by extrusion force, which was the product of stress fatigue. The wear debris is shown in Fig. 12. The debris of the alloy without Si alloying is displayed in Fig. 12a, presenting water ripples on the surface. The wear process can be repeated based on all the above facts presented in Figs. 7a, 11 and 12a: micro-cracks in the subsurface formed under the shear stress, and

39


Fig. 12: Wear debris of alloys (0% Si in as-cast and 0.55wt.% Si in T6 temper)

extended parallelly in a certain depth from the surface, creating a gap between the surface and subsurface. Due to the plastic deformation and instantaneous high temperature caused by local high press, cold welding spot formed between the steel slider and the alloy surface. Along with the slide of the grinding wheel, the local surface of the alloy peeled off. It can be concluded that adhesive wear and fatigue wear are the main wear mechanism of the alloy without Si alloying. The temperature on the surface of the alloy increased rapidly due to the direct contact between the matrix and the steel slider, resulting in the softening effect of the affected layers. The debris of the alloy with 0.55wt.% Si is shown in Fig. 12b. Granulated particles, like globular, cubic or other shapes were the products of abrasive wear. In addition, the dimension of the debris decreased obviously. At this time, abrasive wear became the main wear mechanism.

4

Conclusions

1)

The microstructure refined by Si alloying is the main reason for the increase of hardness. Meanwhile the integrity of the matrix undermined by Si alloying causes the decrease of the tensile strength and elongation.

2)

A α + η + (α+η) mixture formed through T6 heat treatment causes the decrease of the tensile strength. As compared to the as-cast alloy, the heat-treated samples obtain remarkable increase of elongation and hardness. Wear resistance of both the as-cast and T6 treated alloys firstly increases and then decreases with the increase of Si content. With same Si content, wear resistance of the T6 alloy is better than the as-cast. When Si addition reaches 0.55wt.%, wear resistance achieves the best for both as-cast and T6 treated alloys.

3)

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BULETIN - APLINDO No.48/2016 4)

For the as-cast alloy, wear mechanism transforms from adhesive wear and fatigue wear into abrasive wear with the increase of Si content. T6 heat treatment is beneficial to the wear resistance, and abrasive wear is the main wear mechanism.

References [1] Sastry S, Krishna M, Uchil J. A study on damping behaviour of aluminite particulate reinforced ZA-27 alloy metal matrix composites. Journal of Alloys and Compounds, 2001, 314(1):268-274. [2] Li Yuan-dong, Zhang Xin-long, Ma Ying, et al. Effect of mixing rate and temperature on primary Si phase of hypereutectic Al-20Si alloy during controlled diffusion solidification (CDS) process. China Foundry, 2015, 12(3): 173-179. [3] Geng Hao-ran, Tian Xian-fa, Cui Hong-wei, et al. Antifriction and wear behaviour of ZAS35 zinc alloy. Influence of heat treatment and melting technique. Materials Science and Engineering A, 2001, 361: 109114. [4] Chen Fei, Wang Tong - min, Chen Zong - ning, et al . Microstructure, mechanical properties and wear behaviour of Zn-Al-Cu-TiB2 in situ composites. Trans. Nonferrous Met. Soc. China, 2015, 25: 103-111. [5] Bobic Biljana, Bajat Jelena, Aimovic-Pavlovic Zagorka, et al. Corrosion behaviour of thixoformed and heattreated ZA27 alloys in NaCl solution. Trans. Nonferrous Met. Soc. China,2013, 23: 931−941. [6] Chen T J, Hao Y, Sun J. The microstructural and constitutional evolution of cast dendritic ZA27 alloy during partial remelting. Journal of Materials Processing Technology. 2004, 148: 8-14. [7] Chen T J, Hao Y, Sun J, et al. Effects of processing parameters on tensile properties and hardness of thixoformed ZA27 alloy. Materials Science and Engineering A, 2004, 382: 90-103. [8] Tan Yinyuan. Effects of compound modifier on microstructure and performance of ZA27 alloy. Journal of Nanjing University of Science and Technology, 2002, 05: 547-551. [9] Zhu Y H, Man H C, Dorantes-Rosales H J, et al. Ageing characteristics of furnace cooledeutectoid Zn-Al based alloy. Journal of Materials Science, 2003, 38: 2925-2934. [10] Zuo Yu-bo, Liu Xu-dong, Sun Chao, et al. Grain refinement and macrosegregation behavior of direct chill cast Al-Zn-Mg-Cu alloy under combined electromagnetic fields. China Foundry, 2015, 12(5): 333-338. [11] Chen Ti-jun, Li Yuan-dong, Hao Yuan. Effects of Mg and RE additions on the semi-solid microstructure of a zinc alloy ZA27.Science and Technology of Advanced Materials, 2003, 4(6):495-502. [12] Xu Xiao-qing, Li Dr-fu, Guo Sheng-li, et al. Microstructure evolution of Zn-8Cu-0.3Ti alloy during hot deformation. Transactions of Nonferrous Metals Society of China, 2012,22(7): 1606−1612. [13] Chen Ti-jun, Zhang Da-hua, Wang Wei, et al. Effects of Y content on microstructures and mechanical properties of as-cast Mg-Zn-Nd alloys. China Foundry, 2015, 12(5): 339-348. [14] Wang Huai-qing, Si Nai-chao, Si Song-hai, et al. Effect of Ni Alloying on Microstructure and Wear of ZA27 Alloy. Tribiology,2013, 33(1): 57-64. [15] Li Zi - quan, Zhou Heng - zhi, Luo Xin - yi, et al . Aging microstructural characteristics of ZA-27 alloy and SiCp/ZA-27 composite. Trans. Nonferrous Met. Soc. China, 2006, 16: 98-104. [16] Liu Yang, Li Hong-ying, Jiang Hao-fan, et al. Effects of heat treatment on microstructure and mechanical properties of ZA27 alloy. Trans. Nonferrous Met. Soc. China, 2013, 23: 642-649. [17] Wu Yong-yong, Si Nai-chao, Liu Guang-lei, et al. Effect of Mn Alloying on Microstructures and Wear Property of ZA43 Alloy.Foundry, 2014(10): 1019-1023. [18] Babic Miroslav, Aleksandar Vencl, Slobodan Mitrovic, et al.Influence of T4 Heat Treatment on Tribological Behavior of Za27 Alloy Under Lubricated Sliding Condition. Tribol Lett, 2009, 36: 125-134.

41


Effects of grain refinement on cast structure and tensile properties of superalloy K4169 at high pouring temperature Zi-qi Jie 1, Jun Zhang 1, *Tai-wen Huang 1, Lin Liu 1, Hai-jun Su 1, Yan-li Shi 2, and Heng-zhi Fu

1

1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China 2. Xi’an Jiaotong University City College, Xi’an 710072, China

Abstract: In order to improve the filling ability of large complex thin wall castings, the pouring temperature should be increased, but this will result in the grain coarsening. To overcome this problem, two kinds of grain refiners of Co-Fe-Nb and Cr-Fe-Nb ternary alloys, which contain high stability compound particles, were prepared. The effects of the refiners on the as-cast structures and tensile properties of the K4169 superalloy with different casting conditions were studied by analyzing specimens 110 mm long and 20 mm in diameter. Results showed that the mixture addition of the two refiners in the melt of K4169 can reduce the columnar grain region and decrease the equiaxed grain size greatly. After refinement, the amount of Laves phase decreases and its morphology changes from island to blocky structure. The carbides in the fine grain samples are fine and dispersive. Meanwhile, the porosity in specimens is decreased due to grain refinement. As a result, the yield strength, ultimate strength and the elongation of the specimens are increased. The grain refinement mechanisms are also discussed.

Key words : superalloy; K4169; grain refinement; tensile properties CLC numbers: TG143.9

Document code: A

Article ID: 1672-6421(2016)02-101-06

With the continuous improvement of the engine thrust-weight ratio, the turbine disk and the intermediate case in the turbine engine become more complex in structure. Meanwhile, the operating temperature of these superalloy castings reaches approximately 700 °C. Under such a high temperature, a uniform and fine-grained [1, 2] microstructure is desirable in order to obtain good low cycle fatigue resistance and high tensile strength . Therefore, the production of such components challenges metallurgists and requires the development of advanced casting technology. One of the effective methods of improving the filling ability of large-size thin-wall castings is to increase the pouring temperature, but this will lead to a coarse grain size and decrease the low cycle fatigue resistance and tensile strength. The addition of the grain refiners in the melt is an effective way to [1] overcome the problem and to get fine grain size . Grain refinement of as-cast structure means increasing the heterogeneous nucleation sites during the solidification [3] of castings. Fine grain casting techniques of superalloys mainly include the thermal control method , the [1, 4, 5] [6-8] chemical approach and the dynamic method . Among these, the chemical fine grain process is an efficient method, where the heterogeneous nucleation can be increased by the addition of a specially designed master alloy, which contains suitable solid particles with high stability in the melt. This method needs neither complicated equipment nor complex process. Refractory metal oxides, carbides, nitrides and boron have been used as refiners in [1, 9] some superalloys . However, this kind of refiner will introduce inclusions in the castings, which may become [10] crack initiation sites, and deteriorate the mechanical properties . Especially, the addition of boron will decrease [11] [1] incipient melting temperature of the alloys, which reduces the plastic properties greatly . Liu et al developed two kinds of refiners Co-Fe-Nb and Cr-Mo-Nb used in Ni-Fe based super alloys. These refiners possess effective refinement capability without introducing inclusions. However, Co-Fe-Nb and Cr-Mo-Nb can only be used at temperatures of 1,360-1,420 °C, far below the melting and pouring temperatures for most superalloy castings. Ni-based superalloy K4169 is widely used in turbine disk and intermediate case components, due to its high[12, 13] temperature mechanical properties in addition to an excellent corrosion resistance . While the shape of these components tends to become more complex and thin-walled, leading to the bad filling. In order to improve the filling ability of complex and thin-walled castings, the pouring temperature should be increased, but this will result in grain size coarsening. To obtain good filling ability and fine microstructure, two inter-metallic compounds Co3FeNb2 and CrFeNb were prepared as refiners of the K4169 alloy. The constituent elements are also the elements presented in the superalloy K4169, ensuring that the grain refiners do not introduce inclusions and pose any harmful influence on the mechanical properties of the alloy. The effect of grain refiner on cast structure and tensile properties of K4169 at the pouring temperatures of 1,470-1,520 °C was investigated.

* Tai-wen Huang Male, born in 1975, Ph. D., Professor. His research interests mainly focus on superalloys. E-mail: [email protected]

42


1. Materials and experimental procedure Two kinds of ternary alloy grain refiners with the nominal compositions of Co3FeNb2 and CrFeNb were designed and the button ingots of the refiners were prepared by melting an appropriate proportion of the constituents in an arc melting furnace in an argon atmosphere. The raw materials were 99.95% Cr powder, 99.9% Co powder, 99.5% Fe powder and 99.97% Nb block. They were ground into powders with a size of 60-100 μm. The physical and crystallographic parameters of the refiners are listed in Table 1. The melting point of the refiners was analyzed by differential thermal analysis (DTA). The mixture of the two refiners was prepared by mixing physically with the proportion of 1:1 in weight percentage. Table 1: Physical and crystallographic parameters of experimental refiners

Refiner

Crystal structure

Density (g·cm )

Co 3FeNb 2

Hexagonal

8.8

CrFeNb

Hexagonal

8.2

-3

Melting point (°C) 1,550 ﹥1,650

The commercial K4169 alloy with the composition (wt.%): 0.056 C, 0.01 Co, 52.54 Ni, 19.15 Cr, 3.11 Mo, 0.61 Al, 0.94 Ti, 5.03 Nb, 0.0026 B, 0.028 Zr with the balance being Fe was used for the grain refinement experiments. The equilibrium liquidus and solidus temperatures of the alloy are 1,349 and 1,270 °C, respectively, according to DTA results. A vacuum melting furnace was used to cast ingots of K4169 superalloy. The melt was first superheated up to 1,550 °C and held for 2-4 min and then cooled down to the pouring temperature. For the conventional cast samples, the melt was poured into the preheated mold directly. However, for chemical grain refinement samples, the refiner was added into the melt at the pouring temperature. The addition amount was 0.3wt.% of the charge. After that, the melt was stirred for the refiner particles to be dispersed in the melt uniformly. Then the melt was held for 30-60 s for homogenization of the refiner and subsequently poured into the mould. The ceramic moulds with inner size of 120 mm in length and 20 mm in diameter and the preheating temperature of 900 °C were used in all cases. The as-cast ingots were sectioned along the cross-section and the samples were ground, polished and subsequently chemically etched with a solution etchant of 15 g CuSO4, 3.5 ml H2SO4 and 50 ml HCl to expose grain structures. The average equiaxed grain size and fraction of equiaxed grains at transverse cross-section were determined by a standard quantitative metallographic technique. The grain size was measured by the line intercept method and estimated with reference to the ASTM standard. The distribution of the alloying elements was determined using Electron-probe microanalysis (EPMA). The tensile tests were conducted using an Instron 3382 testing machine at room temperature. At least three identical specimens were tested for each case. 2.

Results

The structures of transverse sections of different as-cast samples are shown in Fig. 1. For the samples without grain refinement, only columnar grains were observed. By adding the refiners, an equiaxed grain region was formed and the average grain sizes were reduced. For the samples with the pouring temperature of 1,520 °C,

Fig. 1: Grain structures for different treatment conditions and pouring temperatures: (a) without refiner addition, 1,520 °C,

(b) without refiner addition, 1,470 °C; (c) with refiner addition, 1,520 °C; (d) with refiner addition, 1,470 °C

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BULETIN - APLINDO No.48/2016 after the addition of mixture refiners of the two ternary inter-metallic compounds, the average grain size was refined from 10.56 to 2.84 mm and the proportion of equiaxed grains at cross-section was increased from 10% to 81%. Similar results were obtained for the samples with the pouring temperature of 1,470 °C, where the average grain size was refined from 8.98 to 1.85 mm and the proportion of equiaxed grains was increased from 15% to 93%. The dendritic morphologies are shown in Fig. 2. It can be seen that the dendritic morphologies with highly developed branches were obtained in the case without grain refiner addition. However, the average length of the primary dendrite axes decreases with the addition of the grain refiners. The secondary dendrite arm spacing (SDAS) of both samples (a) and (b) was about 65 μm, and for (c) and (d) was about 58 μm, indicating that the grain refinement has a negligible effect on the SDAS, but the SDAS decreases with the decrease of the pouring temperature.

Fig.2 : Dendritic morphologies for different casting conditions: (a) without refiner addition, 1,520 °C; (b) with addition, 1,520 °C; (c) without refiner addition, 1,470 °C; (d) with addition, 1,470 °C

K4169 superalloy has a wide solidification temperature range. Therefore, porosity is likely to form in its castings. Figure 3 shows the morphology and the distribution of porosity in the samples with the grain sizes of 10.56 mm and 1.85 mm. It was shown that there exist some intensively distributed large-sized porosities in coarse grain samples. However, it becomes uniform and much smaller in the chemically refined specimen

Fig. 3: Porosity of samples with different casting conditions: (a) grain size, 10.56 mm; (b) grain size, 1.85 mm

44

BULETIN - APLINDO No.48/2016 The typical as-cast microstructure of K4169 consists of the primary gamma phase dendrites, carbides, laves and [13] delta phase . Micrographs of laves and MC carbides in test bars of different grain sizes were obtained. In the test bars with the grain size of 10.56 mm and 2.84 mm, block carbides and eutectic laves can be observed. The carbide morphology in the fine grain samples is fine and dispersive. However, the laves phase is mainly contained in the eutectic phase in the coarse grain.

Fig. 4: Microstructure of alloy with different casting conditions: (a) without grain refiner addition, 1,520 °C, grain size 10.56 mm, (b) with refinement, 1,520 °C, grain size 2.84 mm

Figure 5 shows the correlation of grain size and ultimate tensile strength and yield strength obtained at the room temperature tensile tests. The ultimate tensile strength and yield strength of K4169 superalloy are significantly improved along with the grain refinement. When the grain size of K4169 superalloy is decreased from 10.56 mm to 2.84 mm at the pouring temperature of 1,520 °C, the tensile and yield strength are increased by 11.76% and 9.8%, respectively. For the pouring temperature of 1,470 °C, the tensile and yield strength are increased by 19.07% and 29.16%, respectively, corresponding to the grain size decreases from 8.98 mm to 1.85 mm. In addition, the elongation is increased with the addition of grain refiners at different pouring temperatures. At the pouring temperature of 1,520 °C, when the grain size is samples, and the block laves are found in the fine grain samples. The quantity of laves decreases with the decrease of grain size. Besides, the quantity of carbides remained about the same for the same pouring temperature. The results in Fig. 4 show that the volume fraction of laves phase is about 3.35% when the grain size is 10.56 mm. It was reduced to 1.48 % if the grain is refined to 2.84 mm. refined from 10.56 mm to 2.84 mm, the elongation is increased by 53%. When the pouring temperature is 1,470 °C, the elongation is increased by 38% corresponding to the grain size decreases from 8.98 mm to 1.85 mm.

45

BULETIN - APLINDO No.48/2016 3 Discussion Results of this study show that the refiners can lead to grain refinement and increase the proportion of equiaxed grains. The main principle is a fine epitaxial fit between low-index planes of the heterogeneous nucleation particle substrate offered by the grain refiners and the nucleated solid phase. The lower the lattice disregistry, the more effective the refiner will be in promoting nucleation. According to the calculation model of lattice disregistry (δ) [14] between refiners and the nucleated phase proposed by Bramfitt , when the value of δ for some specific crystal [15] planes is less than 12%, the refiner will have a good refining effect. Wang et al calculated and simulated the planes matching models and matching orientations. The results show that (0001) and (0110) planes of refiners Co3FeNb2 and CrFeNb have a fine crystallographic matching relationship with the (110), (111) planes of γ matrix of K4169. Therefore, the refiners can act as the nucleation substrate of γ matrix and allow its epitaxial growth. Presence of a great number of active refiner particles in the melt would cause enormous heterogeneous nuclei of crystallites, which would impinge on one another and restrict further growth. Hence, the formation of numerous nuclei and the restriction on their further growth result in the refinement of grains. However, due to the higher pouring temperature, the refining effect is reduced. It can be seen from Fig. 1 that adding refiner to the melt makes the equiaxed fraction increase along with the grain refinement. The addition of refiner is beneficial for forming the equiaxed grain zone. Additionally, refiner particles dispersed uniformly in the melt causes a large quantity of equiaxed grains formation. The growth of these nuclei will release a great amount of latent heat, which prohibits their further growth. In addition, the formation and growth of many equiaxed grains impede the growth of columnar grains. The decrease of porosity in the specimen with grain refinement is due to the fact that the alloy flow distance is increased with grain refinement. The fluidity of two different conditions is tested by spiral fluidity. The fluidity is [16] 360 mm at the condition of coarse grain and that of the fine grain is 371 mm. Dahle et al also reported that finer grain size should improve fluidity of molten aluminum. This is due to grain refinement postponing dendrite coherency. The important consequence of the solidification in superalloy K4169 is the segregation of Nb and the formation of Laves phase. Laves phase is a brittle inter-metallic topologically close-packed phase with hexagonal structure, [17] known for its detrimental effect on mechanical properties at room temperature . The main reason of laves [17] formation is Nb and Ti segregation . Figure 6 shows the correlation of grain size and segregation ratios in the K4169 superalloy. The segregation ratio is defined as the average concentration in the dendritic core over the average concentration in inter-dendritic region. The segregation ratio close to 1 indicates that the elements can reduce segregation. It can be clearly seen that the segregation of Al, Mo, Cr and Fe has little change, whereas the segregation of Nb and Ti decreases with decreasing grain size. So, this is the most important reason for the decreasing of the quantity of Laves phase.

Fig. 6: Relationship between dendrite segregation ratio and grain size

The increase of the mechanical properties at room temperature in the grain refined samples is mainly due to the increase of the grain boundaries, which inhibits dislocation slide, and increases the yield strength and ultimate

46

BULETIN - APLINDO No.48/2016 strength. At room temperature, the strength of the grain boundary is higher than that of the grain interior

[2, 7, 18]

.

Therefore, the crack propagation would be impeded when encountering a grain boundary. The carbides and Laves phase in fine-grain castings are smaller than those in the coarse grain, which can also increase the yield and ultimate strength. However, high density and large size of micro-porosities in the coarse grain samples will lead to the test bars premature fracture, and cause low elongation and ultimate tensile strength.

4 Conclusions The effects of the refiners on the as-cast structures and tensile properties of K4169 superalloy were studied. The results are summarized as follows: 1.

2. 3. 4.

When adding mixed refiner of Co3FeNb2 and CrFeNb to the melt of K4169 superalloy, the equiaxed grain size could be refined and the proportion of equiaxed grains at cross-section could be increased in the samples with pouring temperature of 1,470- 1,520 °C. Refiner particles with good lattice compatibility with matrix act as substrata of matrix, thereby causing grain refinement. As the grain refines, the amount of Laves phase decreases and its morphology changes from island to blocky structure. The carbides in the fine grain samples are fine and dispersive. The amount of porosity in the specimen could be reduced greatly after grain refinement due to the alloy flow distance being increased with grain refinement. Yield strength and ultimate tensile strength at room temperature increases significantly due to grain refinement.

When the grain size of K4169 superalloy is 1.85 mm, the highest tensile and yield strength obtained are 1,189.32 MPa and 1,138.47 MPa, respectively.peralloy is 1.85 mm, the highest tensile and yield strength obtained are 1,189.32 MPa and 1,138.47 MPa, respectively. References 1.

Liu Lin, Huang Taiwen, Xiong Yuhua, et al. Grain refinement of superalloy k4169 by addition of refiners: cast structure and refinement mechanisms. Materials Science and Engineering A, 2005, 394: 1-8. 2. Du Beining, Yang Jinxia, Cui Chuanyong, et al. Effect of grain refinement on the microstructure and tensile behavior of K417G superalloy. Materials Science and Engineering A, 2015,59-67. 3. Ma Yue, Sun Jiahua, Xie Xishang, et al. An investigation on fine-grain formation and structural character in cast IN718 superalloy. Journal of Materials Processing Technology, 2003,35-39. 4. Xiong Yuhua, Wei Xiuying, Du Jun, et al. Grain refinement of superalloy IN718C by the addition of inoculants. Metallurgical and Materials Transaction A, 2004, 35(7): 2111-2114. 5. Liu Lin, Zhang Rong, Wang Liuding, et al. A new method of fine grained casting for nickle-base superalloys. Journal of Materials Processing Technology, 1998, 77: 300-304. 6. Ma Xiaoping, Li Yingju and Yang Yuansheng. Grain refinement effect of pulsed magnetic field on solidified microstructure of superalloy IN718. Journal of Materials Research, 2009, 24(10): 3174-3181. 7. Wei C N, Bor H Y, Ma C Y, et al. A study of IN713LC superalloy grain refinement effects on microstructure and tensile properties. Materials Chemistry and Physics, 2003, 80(1): 89-93. 8. Jin Wenzhong, Bai Fudong, Li Tingju, et al. Grain refinement of superalloy IN100 under the action of rotary magnetic fields and inoculants. Materials Letters, 2008, 62(10-11): 1585-1588. 9. Bashir S and Thomas M C. Effect of interstitial content on High-temperature fatigue crack propagation and Low-cycle fatigue of alloy 720. Journal of Materials Engineering and Performance, 1993, 2(4): 545-550. 10. Miao Jiashi, Pollock T M and Jones J W. Crystallographic fatigue crack initiation in Nickel-based superalloy Rene′ 88DT at elevated temperature. Acta Materialia, 2009, 57(20): 5964-5974. 11. Liu R, Xi S Q, Kapoor S, et al. Effect of chemical composition on Solidification, microstructure and hardness of Co-Cr-W-Ni and Co-Cr-Mo-Ni alloy systems. IJRRAS, 2010, 5(2): 110-122. 12. Li Ailan, Tang Xin, Gai Qidong, et al. Effect of heat treatment on microstructure of K4169 superalloy. Journal of Aeronautical Materials, 2006, 26(3): 311-312. (In Chinese)

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13. Li Yamin, Liu Hongjun, Liu Jie, et al. Effect of Zr addition on precipitates in K4169 superalloy. China Foundry, 2012, 9(1): 6-10. 14. Bramfitt B L. The effect of carbide and nitride additions on the heterogeneous nucleation behavior of liquid iron. Metallurgical Transactions, 1970, 1(7): 1987-1995. 15. Wang Fu, Zhang Jun, Huang Taiwen, et al. Preparation of inoculants used in superalloy and analysis of the atomic matching models. Journal of Materials Science & Technology, 2013, 29(4): 387-392. 16. Dehle A K, Tondel P A, Paradies C J, et al. Effect of grain refinement on the fluidity of two commercial Al-Si foundry alloys. Metallurgical and Materials Transactions A, 1996, 27(8): 2305-2313. 17. Janaki Ram G D, Venugopal Reddy A, Prasad Rao K, et al. Control of Laves phase in Inconel 718 GTA welds with current pulsing. Science and Technology of Welding & Joining, 2004, 9(5): 390-398. 18. Yang Jinxia, Sun Yuan, Jin Tao, et al. Microstructure and mechanical properties of a Ni-based superalloy with refined grains. Acta Metallurgical Sinica, 2014, 50(7): 839 -844. (In Chinese)

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Data Kendaraan Bermotor 1. Data Kendaran Roda 4 a. Penjualan Kendaraan roda 4 (unit) tahun 2012-2016 di Indonesia No.

Bulan

1 2 3 4 5 6 7 8 9 10 11 12

Januari Februari Maret April Mei Juni Juli Agustus September Oktober Nopember Desember Total

2012 76.427 86.486 87.917 87.144 95.541 101.746 102.511 76.445 102.100 106.754 103.703 89.456 1.116.230

2013

Penjualan (Unit) 2014 2015

96.718 103.609 94.194 103.278 111.824 88.740 95.996 113.067 99.410 102.257 106.124 81.600 99.697 96.872 79.375 104.268 110.614 82.172 112.178 91.334 55.615 77.964 96.652 90.537 115.974 102.572 93.038 112.039 105.222 88.408 111841 91.327 86.937 97.691 78.802 73.264 1.229.901 1.208.019 1.013.290

2016 85.012 88.224 93.990 84.685

351.911

Sumber : Gaikindo

b. Produksi Kendaraan roda 4 (unit) tahun 2012-2016 di Indonesia No.

Bulan

1 2 3 4 5 6 7 8 9 10 11 12


2012 77.036 86.469 85.507 84.426 97.367 94.400 97.330 71.113 94.488 100.298 99.168 77.955 1.065.557

Produksi (Unit) 2013 2014 97.793 104.728 100.491 112.501 89.073 123.007 101.805 121.114 99.661 94.353 97.939 117.309 106.519 93.613 77.354 105.259 116.974 119.346 115.533 116.654 110.570 102.423 94.499 88.216 1.208.211 1.298.523

2015 99.102 93.113 108.066

2016 91.068 91.529 102.483

97.676 89.579 91.807 59.225 103.567 104.702 95.731 88.493 67.719 1.098.780

103.089

388.169

49

BULETIN - APLINDO No.48/2016 b. Penjualan Kendaraan roda 4 (unit) tahun 2012-2016 di ASEAN Penjualan (Unit) No.

Bulan

1

Brunai

2 3 4 5 6 7

Indonesia Malaysia Philipina Singapura Thailand Vietnam

2012 18.634 1.116.230 627.753 156.654 37.247 1.436.335 80.453 3.473.306

Total

2013 18.642 1.229.901 655.793 181.738 34.111 1.330.672 98.649 3.549.506

2014

2015

18.114 1.208.019 666.465 234.747 47.443 881.832 133.588 3.190.208

14.406 1.013.291 666.674 288.609 78.609 799.632 209.267 3.070.488

Jan-April 2016 3.843 351.911 173.432 104.176 35.286 236.546 79.218 984.412

sumber : AAF

c. Produksi Kendaraan roda 4 (unit) tahun 2012-2016 di ASEAN Produksi (Unit) No. 1 2 3 4 5

Bulan Indonesia Malaysia Philipina Thailand Vietnam Total

2012

2013

2014

1.065.557 1.208.211 569.620 601.407 75.413 79.169 2.453.717 2.457.057 73.673 93.630 4.237.980 4.439.474

1.298.523 596.418 88.845 1.880.007 121.084 3.984.877

2015

1.098.780 614.664 98.768 1.913.002 171.753 3.896.967

Jan-April

2016 388.169 174.385 33.833 645.111 68.581 1.310.079

sumber : AAF

2. Data Kendaraan Roda 2 / Sepeda Motor a.

Penjualan sepeda motor 2012-2016 Di Indonesia Penjualan (Unit)

No.

Bulan

Jan-April 2012

1 2 3 4 5 6 7 8 9 10 11 12


652.601 670.757 626.689 622.929 619.540 550.468 585.658 433.741 628.739 634.575 627.048 488.841 7.141.586 sumber : AISI Diolah

2013

2014

649.983 580.288 653.357 681.267 657.483 728.820 660.505 729.279 647.215 734.030 661.282 753.789 704.019 539.171 490.824 599.250 678.139 706.938 717.272 675.962 688.527 592.635 552.408 556.586 7.771.014 7.908.914

2015

2016 443.449 551.930 583.339 501.564

513.816 570.524 562.185 538.746 482.691 588.675 439.245 645.997 632.227 626.725 565.066 542.487 6.708.384 2.080.282

50


b.

Produksi sepeda motor 2012-2016 Di Indonesia

No. Bulan

Produksi (Unit) Jan-April

2012 2013 2014 1 Januari 685.688 662.920 595.636 2 Februari 665.570 659.417 659.258 3 Maret 606.984 654.760 729.476 4 April 619.839 672.370 748.401 5 Mei 619.829 644.881 722.192 6 Juni 535.621 653.384 761.117 7 Juli 577.488 694.492 553.626 8 Agustus 428.662 484.428 611.235 9 September 620.250 683.066 747.992 10 Oktober 627.352 729.876 686.101 11 Nopember 625.865 691.115 598.560 12 Desember 466.573 549.586 512.510 Total 7.079.721 7.780.295 7.926.104

2015 2016 524.368 315.994 552.543 382.495 593.592 460.731 563.566 378.315 483.872 559.956 290.972 450.719 445.301 475.758 429.630 328.361 5.698.637 1.537.535

sumber : AISI Diolah

c.

Penjualan sepeda motor 2012-2016 di ASEAN Penjualan (Unit)

No. 1 2 3 4 5

Bulan Indonesia Malaysia Philipina Singapura Thailand Total

2012

2013

2014

2015

7.771.014 7.908.014 7.141.586 494.586 537.753 546.719 442.749 731.130 702.599 752.835 790.245 8.046 9.923 11.650 8.145 2.007.383 2.130.067 2.004.498 1.701.535 11.284.680 10.521.928 11.086.716 10.851.615

8,043,535

Jan-April

2016 2.080.282 139.289 351.102 2.656 535.500 3.108.829

sumber : AAF

d. Produksi sepeda motor 2012-2016 Di ASEAN Produksi (Unit) No. 1 2 3 4

Bulan

2012

Indonesia 7.780.295 Malaysia 549.244 Philipina 729.480 Thailand 2.218.625 Total 11.277.644

2013

7.926.104 439.907 755.184 1.842.708 10.963.903

2014

5.698.637 382.218 795.840 1.807.325 8.684.020

2015

5.698.637 382.218 795.840 1.807.325 8.684.020

Jan-April

2016 1.537.535 137.156 319.225 583.451 2.577.367

sumber : AAF

51

BULETIN - APLINDO No.48/2016 Informasi Umum & Pameran A.

B.

Web site Pemerintah yang dapat diakses : 1.

www.setneg.go.id (Sekretariat Negara)

2.

www.kemenperin.go.id (Kementerian Perindustrian)

3.

www.kemenkeu.go.id (Kementerian Keuangan)

4.

www.kemendag.go.id (Kementerian Perdagangan)

5.

www.beacukai.go.id (Direktorat Bea & Cukai, Kementerian Keuangan)

6.

www.esdm.go.id (Kementerian ESDM)

7.

www.bkpm.go.id (Badan Koordinasi Penanaman Modal)

8.

www.bps.go.id (Biro Pusat Statistik)

Web site Asosiasi Industri Pengecoran Logam Indonesia (APLINDO) Kini APLINDO telah tersedia Web site sendiri : www.aplindo.web.id, mohon dukungan partisipasi aktif Bapak-bapak sekalian dan diharapkan saran, masukan, permasalahan dan perkembangan yang terjadi di industri pengecoran logam di Indonesia. Saran dan masukan anda dapat berupa artikel ke alamat [email protected]

C.

Web site Himpunan Ahli Pengecoran Logam Indonesia Kini HAPLI telah tersedia Web-site sendiri : http://hapli.wordpress.com/ , mohon dukungan partisipasi aktif Bapak-bapak sekalian dan diharapkan saran serta masukan anda berupa artikel sesuai page yang tersedia dalam format *.doc ke alamat [email protected] untuk diupload, ataupun komentar langsung anda pada Blog.

D. Pameran dan Seminar 1.

5th Metal & Steel/FABEX Saudi Arabia Exhibition: 1 May 2016 - 4 May 2016 Riyadh Int Convention and Exhibition Centre www.arabian-german.com/

2.

Metal & Metallurgy China: 17 May 2016 - 20 May 2016 China International Exhibition Center, Beijing www.mm-china.com/en/

3.

21-25 May, 2016 The 72nd World Foundry Congress 2016, Nagoya, Japan, This intellectually and professionally stimulating biennial congress offers you a golden

52

BULETIN - APLINDO No.48/2016 opportunity to meet fellow foundrymen from all over the world and exchange ideas in order to develop a common vision for the future of the global foundry industry. The WFC2016 will have presentations of technical papers and meetings as well as enjoyable social events.through which you can learn more about traditional Japanese culture. The WFC2016 will be held in Nagoya,Japan’s third largest metropolitan region located on central Honshu. Nagoya is known as one of the centres of the manufacturing industry and also for its famous historical castle. Nagoya Castle, built by the first shougun of the Tokugawa shougunate, has a pair of golden shachihoko (carp-like mythical animals) on its roof, and they have become the symbol of Nagoya.

www.wfc2016.jp 4.

China Diecasting: 12 Jul 2016 - 14 Jul 2016 Shanghai, China Diecasting exhibition. www.diecastexpo.cn/en/

5.

Indometal , 25-27 Oct 2016 Jakarta International Expo Kemayoran, Indonesia International Metal & Steel Trade Fair for Southeast asia www.indometal.net

6.

ANKIROS/ANNOFER/TURKCAST 2016: 29 Sep 2016 - 1 Oct 2016 TUYAP Fair Ground, Istanbul, Turkey International exhibition of metal casting companies and foundry supply companies. www.ankiros.com

7.

The 24th Annual International Scientile and Technical Conference “Foundry Production and Metallurgy 2016, 19-21 October 2016 Binsk, BNTU (Belarus National Technical University) Belarus

8.

Manufacturing Indonesia 2016 Jakarta International Expo Kemayoran, Indonesia The 27th International Manufacturing, Machinery, Equipment, Material and Services Exhibition WWW.manufacturingindonesia.com

9.

Alucast 2016: 1 Dec 2016 - 3 Dec 2016 Bangalore, India Diecasting Exhibition. www.alucast2016.com

53

APLINDO. Asosiasi Industri Pengecoran Logam Indonesia

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