Study Effect of Holding Time at Post Weld Heat Treatment (PWHT) on Joint Dissimilar Welding ASTM 335 P11 to ASTM 304L under Controlled Condition

Abstract

Welding joint Austenitic stainless steels can undergo intergranular corrosion attack in some service conditions, such as oil refineries, petrochemical plants, and industrial furnaces operating at high temperatures (between 500°C and 675°C). This research focuses on fabricating dissimilar metal welds to avoid failure due to sensitization and investigate stress-relieved carbon steel by Post-weld heat treatment (PWHT). This work studies a dissimilar weld joint (DWJ) of ASTM 335 grade P11 joint to ASTM 304L and PWHT after welding. These welding processes are used in multi-pass gas tungsten arc welding (GTAW) using filler metal R309L. PWHT at temperatures of 550 °C with holding times of 40, 50, and 60 minutes and then slow cooling in atmospheric air temperature, It was used to compare the results holding time carbon steel ASTM A335 Gr. P11 while processing. Holding time at 50 minutes has the maximum result of PWHT with 182 HV and has a good distribution of perlite with fine grain and increasing holding time also increases formed carbide on the grain boundary of stainless steel 304L.