Structural analysis by SEM-EBSD of the transverse section of the dissimilar weld SASS AL-6XN–DSS 2205

This study presents a detailed microstructural analysis of a dissimilar welded joint between duplex stainless steel (DSS) 2205 and super-austenitic stainless steel (SASS) AL-6XN using electron backscattered diffraction (EBSD) in the scanning electron microscope (SEM). The joint was welded with ER-NiCrMo3 filler wire using gas metal arc welding (GMAW) with spray transfer mode and 1.6 kJ/mm heat input. The microstructure of the base materials (BM) revealed equiaxed austenitic grains in AL-6XN and an approximate 50:50 ratio of elongated austenite and ferrite grains in DSS 2205. Notably, the heat-affected zone (HAZ) in DSS 2205 showed random texture due to ferritization and grain coarsening. EBSD analysis at the interfaces revealed epitaxial grain growth from partially melted grains while energy-dispersive X-ray maps disclosed complex interdendritic particles in the weld metal (WM). Vickers microhardness profiles were correlated with the observed microstructural features across the welded joint.

Texture and Microstructure of the Transverse Section in AL6XN/2205 Dissimilar Welds via EBSD.