Abstract
The impact of heat input on dissimilar welded joints plates composed of stainless (Stnls) steel (SS304L) and duplex Stnls steel (DSS 2205) is the prime segment of this study. When employing ER309L & ER 2209 filler in the gas filled tungsten arc welding (GTAW), one heat input was chosen as the higher heat input (HHI) (1.404 kJ/mm) that was desired. Heat input ranged from 150-195A with 14-16V voltage. Both the HAZ and the weld zone exhibit macro segregation, resembling islands and peninsulas. The ferrite content of the HHI weld zone falls as heat input rises. However, austenite nucleation in the HAZ was positively impacted by HHI. The 309L HAZ micro-hardness increases from 203.63 Hv 0.5 to 281.91 Hv 0.5; likewise, the 2209 filler micro-hardness increases from 246.72 Hv 0.5 to 283.94 Hv 0.5 horizontally from WZ to HAZ. For 309L and 2209 filler, the HHI weldments’ tensile strength parameter, or maximum force, was 27052N and 27389.8N, respectively. Observation of WA, PTA, GBA, RA found during characterization. During impact test fracture analysis we observe parabolic dimples, teat ridges, micro voids which emboldened the high ductile nature of the joint. Ferrite-austenite phase transformation has sought secondary austenite in the post weld coupon. Tests like the tensile testing; Charpy impact testing and Vickers micro-hardness testing were performed to determine mechanical properties of the dissimilar metal welds (DMWs).
Keywords: Dissimilar Weld, Duplex Stainless Steel, Filler Metal, High Heat Input, Microstructure.