DAFTAR ISI HALAMAN JUDUL ............................................................................................ i LEMBAR PENGESAHAN DOSEN .................................................................... ii LEMBAR PENGESAHAN DOSEN PENGUJI .................................................. iii HALAMAN PERSEMBAHAN .......................................................................... iv HALAMAN MOTTO .......................................................................................... v KATA PENGANTAR ........................................................................................ vi ABSTRAK ....................................................................................................... viii DAFTAR ISI ....................................................................................................... x DAFTAR TABEL ............................................................................................. xii DAFTAR GAMBAR ........................................................................................ xiii DAFTAR NOTASI ............................................................................................ xv BAB I PENDAHULUAN .................................................................................... 1 1.1 Latar Belakang ........................................................................................... 1 1.2 Rumusan Masalah ...................................................................................... 2 1.3 Batasan Masalah ......................................................................................... 3 1.4 Tujuan Penelitian ........................................................................................ 3 1.5 Manfaat Penelitian ...................................................................................... 3 1.6 Sistematika Laporan ................................................................................... 4
BAB II TINJAUAN PUSTAKA .......................................................................... 5 2.1 Kajian Pustaka ............................................................................................ 5 2.2 Dasar Teori ................................................................................................. 7 2.2.1 Definisi Pengelasan .............................................................................. 7 2.2.2 Dasar Teori Resistance Spot Welding (RSW) ....................................... 7 2.2.3 Las Titik .............................................................................................. 9 2.2.4 Metalurgi Las (Nugget) ...................................................................... 10 2.2.5 Mode Patah ........................................................................................ 12 2.2.6 Metalurgi Serbuk (Powder Metallurgy) .............................................. 15 2.2.7 Distribusi Ukuran Partikel .................................................................. 16 2.2.8 Definisi Baja Karbon Rendah ............................................................. 18 x
2.2.9 Definisi Aluminium ........................................................................... 20 2.2.10 Klasifikasi Aluminium ..................................................................... 21 BAB III METODOLOGI PENELITIAN............................................................ 28 3.1 Flow Chart ............................................................................................... 28 3.2 Bahan dan Alat ......................................................................................... 29 3.3 Proses Pengelasan ..................................................................................... 30 3.3.1 Pembuatan Filler................................................................................ 30 3.3.2 Proses Pengayakan ( Screening ) ........................................................ 31 3.3.3 Komposisi Filler ................................................................................ 32 3.3.4 Pembuatan Lubang............................................................................. 34 3.3.5 Parameter Penelitian dan Dimensi Spesimen ...................................... 34 3.4 Pengujian.................................................................................................. 36 3.4.1 Pengujian Tarik/Geser ........................................................................ 36 3.4.2 Pengujian Foto Mikro dan Makro ....................................................... 37 3.4.3 Pengujian Kekerasan .......................................................................... 38 BAB IV HASIL DAN PEMBAHASAN ............................................................ 40 4.1 Pengujian Foto Makro dan Mikro ............................................................. 40 4.1.1 Pengujian Foto Makro ........................................................................ 40 4.1.2 Pengujian Foto Mikro ........................................................................ 42 4.2 Pengujian Tarik-Geser (Tensile-Shear Test) .............................................. 50 4.3 Pengujian Kekerasan Vickers .................................................................... 53 BAB V PENUTUP ............................................................................................ 59 5.1 Kesimpulan .............................................................................................. 59 5.2 Saran ........................................................................................................ 60 DAFTAR PUSTAKA ........................................................................................ 61 LAMPIRAN ...................................................................................................... 63
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DAFTAR TABEL Tabel 2.1 Ukuran Standart Teknik Pengayakan .................................................. 18 Tabel 2.2 Klasifikasi Baja Karbon...................................................................... 19 Tabel 2.3 Komposisi Aluminium seri 1xxx ........................................................ 22 Tabel 2.4 Komposisi Aluminium seri 2xxx ........................................................ 23 Tabel 2.5 Komposisi Aluminium seri 3xxx ........................................................ 23 Tabel 2.6 Komposisi Aluminium seri 4xxx ........................................................ 24 Tabel 2.7 Komposisi Aluminium seri 5xxx ........................................................ 25 Tabel 2.8 Komposisi Aluminium seri 6xxx ........................................................ 26 Tabel 2.9 Komposisi Aluminium seri 7xxx ........................................................ 27 Tabel 3.1 Alat Yang Digunakan ......................................................................... 29 Tabel 3.2 Komposisi Berat Massa Serbuk .......................................................... 33 Tabel 3.3 Berat Massa Pada Variasi Komposisi Filler ........................................ 33 Tabel 3.4 Parameter Penelitian ........................................................................... 35 Tabel 4.1 Hasil Pengujian Foto Makro Pengelasan RSW.................................... 40 Tabel 4.2 Hasil Pengujian Foto Mikro Pada Daerah Fe (Fe 90% : Al 10%) ........ 42 Tabel 4.3 Hasil Pengujian Foto Mikro Pada Daerah Al (Fe 90% : Al 10%) ........ 43 Tabel 4.4 Hasil Pengujian Foto Mikro Pada Daerah Fe (Fe 70% : Al 30%) ........ 44 Tabel 4.5 Hasil Pengujian Foto Mikro Pada Daerah Al (Fe 70% : Al 30%) ........ 45 Tabel 4.6 Hasil Pengujian Foto Mikro Pada Daerah Fe (Fe 30% : Al 70%) ........ 46 Tabel 4.7 Hasil Pengujian Foto Mikro Pada Daerah Al (Fe 30% : Al 70%) ........ 47 Tabel 4.8 Hasil Pengujian Foto Mikro Pada Daerah Fe (Fe 10% : Al 90%) ........ 48 Tabel 4.9 Hasil Pengujian Foto Mikro Pada Daerah Al (Fe 10% : Al 90%) ........ 49 Tabel 4.10 Spesimen Hasil Pengujian Tarik-Geser (Tensile-Shear Test) Menggunakan Filler........................................................................................... 51
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Tabel 4.11 Spesimen Hasil Pengujian Tarik-Geser (Tensile-Shear Test) Tidak Menggunakan Filler........................................................................................... 51
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DAFTAR GAMBAR
Gambar 2.1.
Ketebalan Bahan Transisi ............................................................ 6
Gambar 2.2.
Diagram Alat Las Listrik ............................................................ 10
Gambar 2.3.
Nugget Las Titik ......................................................................... 11
Gambar 2.4.
Prediksi Diameter Kritis Berdasarkan Model Patah Interfacial dan Pullout ........................................................................................ 12
Gambar 2.5.
Bentuk Patahan Uji Geser/Tarik ................................................. 12
Gambar 2.6.
Diameter Kritis Untuk Uji Tarik dan Uji Tarik-Geser ................. 13
Gambar 2.7.
Prediksi Gagal PF dan IF Berdasarkan Ketebalan Material.......... 14
Gambar 2.8.
Proses Reaksi Kimia ................................................................... 16
Gambar 2.9.
Peralatan Uji Ayakan .................................................................. 17
Gambar 2.10. Distribusi Ukuran Partikel........................................................... 17 Gambar 3.1.
Flow Chart Skema Penelitian ..................................................... 28
Gambar 3.2.
Alat Spot Welding ...................................................................... 30
Gambar 3.3.
Kikir Manual ............................................................................. 30
Gambar 3.4.
Serbuk Aluminium Paduan Al5083 ............................................ 31
Gambar 3.5.
Serbuk Baja SS400 .................................................................... 31
Gambar 3.6.
Alat Pengayak Serbuk ................................................................ 32
Gambar 3.7.
Alat Pemisah Ukuran Partikel .................................................... 32
Gambar 3.8.
Timbangan Digital ..................................................................... 33
Gambar 3.9.
Mesin Frais Manual ................................................................... 34
Gambar 3.10. Ukuran Diameter Lubang Filler ................................................. 34 Gambar 3.11. Dimensi Spesimen ..................................................................... 35 Gambar 3.12. Alat Pengujian Tarik/Geser ........................................................ 36 Gambar 3.13. Alat Pengujian Foto Mikro ......................................................... 37 Gambar 3.14. Alat Pengujian Foto Makro ........................................................ 38 Gambar 3.15. Alat Pengujian Kekerasan Mikro Vickers Hardness ................... 39 Gambar 4.1.
Spesimen Uji Tarik-Geser .......................................................... 50
Gambar 4.2.
Grafik Hasil Pengujian Tarik-Geser Pengelasan RSW Menggunakan Filler .................................................................. 52
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Gambar 4.3.
Grafik Hasil Pengujian Tarik-Geser Pengelasan RSW Tidak Menggunakan Filler .................................................................. 53
Gambar 4.4.
Grafik Kekerasan Variasi Mesh 100 Komposisi Fe 90% : Al 10% ................................................................................................... 54
Gambar 4.5.
Grafik Kekerasan Variasi Mesh 100 Komposisi Fe 70% : Al 30% ................................................................................................... 55
Gambar 4.6.
Grafik Kekerasan Variasi Mesh 100 Komposisi Fe 30% : Al 70% ................................................................................................... 56
Gambar 4.7.
Grafik Kekerasan Variasi Mesh 100 Komposisi Fe 10% : Al 90% ................................................................................................... 57
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DAFTAR NOTASI
Persamaan 2.1.
Persamaan Jumlah Energi Termal ..................................... 8
Persamaan 2.2.
Persamaan Beban Patah Pada Kondisi Interfacial (IF) ..... 13
Persamaan 2.3.
Persamaan Beban Patah Pada Kondisi Pullout (PF) ......... 13
Persamaan 2.4.
Persamaan Diameter Kritis ............................................. 13
Persamaan 2.5.
Persamaan Prediksi Kegagalan Interfacial (IF) ................ 13
Persamaan 2.6.
Persamaan Prediksi Kegagalan Pullout (PF) .................... 14
Persamaan 3.1.
Persamaan Tegangan Tarik.............................................. 36
Persamaan 3.2.
Persamaan Vickers Hardness Number ............................ 38
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DAFTAR LAMPIRAN
Lampiran 1
Hasil Uji Tarik
Lampiran 2
Harga Kekerasan Mikro Vickers
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