Evaluate the effect of controlled welding parameters on microstructural characteristics and micro-hardness for stainless steel 304 by using TIG and SMAW welding process

Abstract EN

This paper investigated the effect of the welding process of Shielded Metal Arc Welding (SMAW) and the relatively Tungsten-inert gas welding (TIG) process on 304 Austenitic Stainless steel.

The welding process was carried out on 4mm thick plate of 304 Stainless Steel using SMAW and TIG welding processes.

The two set of plates having the single plate size of 350mm×26mm×4mm were welded using Tungsten Inert Gas welding and Shielded metal arc welding process.

At the varied welding heat input, no noticeable modification of - phase throughout the microstructure was observed, only variations in grain size of austenite could be noticed.

Also, inclusions and porosities in form of dark dots were noticed in some of the microstructures, none of micro-cracklings were encountered during the investigation.

Weld solidification cracking were present as white stretches in microstructures of the HAZ samples evaluated.

Further it is observed from the optical micrographs shown that the extent of grain coarsening in the HAZ increases with increase in heat input.