Analysis of dissimilar weldeing of austenitic stainless steel to low carbon steel by TIG welding process
In the current study, the effect of heat treatment on the dissimilar metal welding of austenitic stainless steel (AISI 304L) and low carbon ferritic steel (AISI 1005) using Tungsten Inert Gas (TIG) welding process was investigated with a view to minimize and/ or eliminate the previously reported danger of inhomogeneous hardness distribution experienced across the fusion zone. Heat treatment (Normalizing) of the as welded dissimilar metal was carried out in a muffle furnace at temperatures ranging from 7500C to 8500C and held for varied length of time. Micro structural evaluation and mechanical properties of the fusion zone (FZ), heat affected zone (HAZ) and the base metals (BM) were performed using microscopy and micro hardness evaluation. The result shows that for dissimilar metal weldment, the non-uniform hardness distribution in the fusion zone can be essentially eliminated by using appropriate post weld heat treatment.