Impact of Post Welding Heat Treatment Process on Microstructure and Mechanical Properties of TIG Welded SS-304 & SS316l Dissimilar Metals

Abstract

Abstract: The present work aims at improvising the mechanical properties of the weldments under different heating conditions. Two materials SS304 and 316L are joined under various parameters like current, gas flow rate, and root gap. The weldments are post heated to a temperature of 800⁰C in a muffle furnace to improve the mechanical properties at fusion zone HAZ and parent materials. The microstructure of the specimens at different zones is studied under 500x magnification which revealed the formation of dendritic structure and austenitic grain boundaries with annealing twins showing elongated grains with ASTM No 7 and 8 at SS304 base material, Fusion zone, and SS316L parent material.

Index Terms: hardness, microstructure, welding, weldments, base metal.