ANALISIS GAP DAN METODE OSILASI FIBER LASER WELDING PADA MATERIAL FERRITIC STAINLESS STEEL DIN 1.4003 TERHADAP SIFAT MEKANIK DAN STRUKTUR MIKRO

Abstract

The transportation manufacturing industry, including PT X (Persero) as a train
manufacturer in Indonesia, played a crucial role in the country's economic growth. Stainless steel were
used as the primary material in their production, which is a corrosion-resistant type of steel with high
durability. This study focuses on using laser beam welding in exchange with GMAW while considering
the gap size and oscillation method to achieve optimal joints on Ferritic Stainless Steel DIN 1.4003.
Large gap sizes made welding process difficult. The conducted tests in this research include tensile
tests, hardness tests, metallography test, and SEM characterization tests. The highest hardness value
has found in the weld metal region, specifically in specimen with 0.5 mm gap and triangular oscillation
method with the value of 361.64 kgf/mm2

. The high hardness is attributed to the phase change into
martensite. In the tensile tests, highest tensile strength produced in specimen with 0.5 mm gap and line
oscillation method with average value of 402.175 MPa. This value was not accepted because it is less
than the tensile strength value of the parent material. All specimens from different variations fractured
at the weld metal region due to the incomplete penetration, which was also be observed in the macro
test results. The welding penetration tended to be sideward, both to the left and right, because of the
excessive width used. In the SEM characterization test that has been conducted, the surface texture of
the specimens was observed, with the fusion line having a smoother texture than the weld metal region.
The study's results did not show significant differences concerning the use of the triangular oscillation
method or the line oscillation method.