Analisis Karakteristik Struktur Mikro Pada Sambungan Las GTAW dengan Perbedaan Material

Abstract

Along with the rapid advancement of technology, innovation in the field of engineering materials has also increased significantly, one of which is in the technique of joining two different types of materials or known as dissimilar welding. This study aims to evaluate the effect of variations in the type of filler metal on the microstructure of the joint and the extent to which these variations affect the tensile strength of the welding results between 316L stainless steel and St 41 carbon steel. The method used in this study is an experimental method with a microstructure observation approach to analyze microstructural changes that occur in the weld metal, parent metal, and heat-affected zone (HAZ) due to the use of different fillers.

The results of the observation show that the use of ER309L filler produces a microstructure in the weld metal with finer carbide grains compared to ER70S and ER316L fillers, which tend to produce larger grains. This difference in microstructure has a significant impact on mechanical performance, especially the tensile strength of the weld joint. This shows that the selection of filler type greatly affects the quality of the welding results when viewed in terms of microstructure.

The authors recommend the use of ER309L type filler for dissimilar welding between the two materials, with the note that the test specimens meet the ASTM E8 tensile testing standard to ensure representative and technically acceptable results.