Transformaciones microestructurales en soldaduras disímiles de acero inoxidable austenítico con acero inoxidable ferrítico

Abstract

This research studies the metallurgical transformations taking place the SMAW welding of AISI 316L austenitic stainless steel with AISI 430 ferritic stainless steel. To perform the study were used two different electrodes, AWS E309L austenitic and AWS E2209-16 duplex stainless steels 3.2 mm diameter. The joints were made with a single-pass welding including current and welding speed variations; the low values were 49 A and 2,4 mm.s–1 and the high values were 107 A and 4,3 mm.s –1. This study evaluated the influence of the type of electrode and the welding parameters on the microstructural evolution of heat affected and fusion zones. Also, differences were found on morphology and delta ferrite amount for all weld metals. The heat affected zone of the ferritic side showed grain coarsening and grain refinement with martensite at the grain boundaries. Tensile strength was similar for all welded joints.