Microstructural and weldability analysis of Inconel617/AISI 310 stainless steel dissimilar welds

• Inconel 617 filler metal showed the highest resistance to solidification cracking.
• Cracking occurred in the HAZ of joints using Inconel 82 and 310SS filler metals.
• Weldability was affected by Solidification temperature range and remaining liquid film.

In this study, the microstructural evolutions and weldability of the Inconel 617/310 austenitic stainless steel dissimilar welds were investigated. Three types of filler materials including Inconel 82, Inconel 617 and 310 austenitic stainless steel were used to fabricate dissimilar joints using the gas tungsten arc welding process. Microstructural observations showed distinct cracks in the weldment produced by 310 austenitic stainless steel filler metal. The results of varestraint weldability test showed that the joints produced by Inconel 617 and 310 stainless steel filler metals exhibited the highest and lowest resistance to solidification cracking, respectively. The relatively poor cracking resistance of the welds prepared by 310 stainless steel was attributed to the wide solidification temperature range and presence of low melting point secondary phases.