PENGARUH INTERLAYER PB DENGAN VARIASI HEAT TREATMENT TERHADAP STRUKTUR MIKRO DAN SIFAT MEKANIK SAMBUNGAN FSSW AA1100

ABSTRAK
Aluminium Paduan digunakan dalam berbagai sektor industri, terutama pada
bidang kedirgantaraan dan otomotif karena kekuatan spesifikasinya yang tinggi.
Penelitian ini mengkaji pengaruh interlayer Pb dengan variasi waktu heat treatment
terhadap terbentuknya cacat hook defect. Material plat Al AA1100 dengan dimensi
125 x 40 x 2 mm disambung dengan menggunakan mesin frais Optimum
Maschinen Germany MT 100 (daya rotor 2,2 kW, kecepatan spindel 1600 rpm) tool
pin berdiameter 18 mm, kecepatan putar 1600 rpm, kedalaman penetrasi 2,75 mm,
pada variasi waktu heat treatment 12, 14, 16, dan 18 detik dilakukan menggunakan
blow torch. Pengujian tarik-geser menggunakan Universal Testing Machine (UTM)
standar SNI 8389:2017. Pengujian struktur mikro dilakukan menggunakan
mikroskop Holland microscope serta etsa menggunakan larutan Modified Poulton
Reagent (30 mL HCl, 40 mL HNO₃, 2,5 mL HF, 42,5 mL H₂O, dan 12gram CrO₃).
Hasil pengujian tarik-geser menunjukkan nilai tertinggi sebesar 29,28 MPa pada
heat treatment 16 detik, sedangkan nilai terendah sebesar 18,54 MPa pada heat
treatment 18 detik. Hasil pengujian struktur mikro menunjukkan bahwa
peningkatan waktu heat treatment menyebabkan difusi Pb ke dalam aluminium
semakin meningkat dan batas antarmuka Al–Pb menjadi semakin kabur. Kondisi
struktur mikro paling homogen diperoleh pada heat treatment 16 detik, sedangkan
pada 18 detik terlihat perubahan mikrostruktur yang lebih besar. Penambahan
interlayer Pb dengan variasi heat treatment terbukti mampu meningkatkan kualitas
sambungan dan mengatasi hook defect.
Kata kunci: AA1100, FSSW, interlayer Pb, Hook Defect, heat treatmen

ABSTRACT
Aluminum alloys are widely used in various industrial sectors, particularly in
aerospace and automotive applications, due to their high specific strength. This
study investigates the effect of Pb interlayer with varying heat treatment durations
on the formation of hook defects. Aluminum AA1100 plates with dimensions of 125
× 40 × 2 mm were joined using an Optimum Maschinen Germany MT 100 milling
machine (rotor power 2.2 kW, spindle speed 1600 rpm) and a pin tool with a
diameter of 18 mm, rotational speed of 1600 rpm, and penetration depth of 2.75
mm. Heat treatment was applied using a blow torch for durations of 12, 14, 16, and
18 seconds. Shear tensile testing was conducted using a Universal Testing Machine
(UTM) in accordance with SNI 8389:2017 standards. Microstructural analysis was
performed using a Holland microscope, with etching carried out using Modified
Poulton Reagent (30 mL HCl, 40 mL HNO₃, 2.5 mL HF, 42.5 mL H₂O, and 12 g
CrO₃). The shear tensile test results showed the highest strength of 29.28 MPa at
16 seconds of heat treatment, while the lowest strength of 18.54 MPa was observed
at 18 seconds. Microstructural examination revealed that increasing heat treatment
duration enhanced Pb diffusion into aluminum, resulting in a more indistinct Al–
Pb interface. The most homogeneous microstructure was obtained at 16 seconds of
heat treatment, whereas at 18 seconds, more pronounced microstructural changes
were observed. The addition of a Pb interlayer combined with controlled heat
treatment proved effective in improving joint quality and mitigating hook defects.
Kata kunci: AA1100, FSSW, Interlayer Pb, Hook Defect, Heat Treatment.