Effect of weaving speed on mechanical properties of stainless steel 316L pipe in orbital gas tungsten arc welding

Abstract This study uses 5G welding to weld GTAW orbital pipes without metal filler (autogenous) on SS316L stainless steel pipes. The test specimen is 3 mm thick and 114 mm wide. The test begins with welding specimen preparation. Orbital pipe welding is done counterclockwise with a 100A welding current, 1.4 mm/s welding speed, and three weaving speeds: 0.150, 0.154, and 0.161. Tensile tests were performed at 0°, 90°, 180°, and 270° with tension-type A&D RTF-2350 machines, while Vickers microhardness tests were only performed at 180°. The tensile test data shows that all fractures occur in the weld area, with the highest tensile strength at 571.07 MPa at 0.150 mm/s and 180° angular orientation. Weld metal (WM), heat-affected zone (HAZ), and base metal (BM) microhardness were examined. At 0.161 mm/s, the WM region had the highest average value of 148.47 HV, while the HAZ had 147.06 HV. Microhardness in the BM region is stable at all three weaving speeds from 164.98 to 169.36 HV. The maximum microhardness was 169.36 HV at 0.150 mm/s weaving speed. This study found that the higher the weaving speed, the tighter the weld pool produced and the higher the microhardness value in the WM and HAZ areas, but lower in the BM area.