Solidification crack susceptibility of Nb–bearing austenitic stainless steel weld metals

The effect of niobium on the solidification crack susceptibility of austenitic stainless steel weld metals has been investigated using both the solidification cycle hot–tension test, with a Gleeble–1500 simulator, and the Trans–varestraint test. The results indicated that solidification crack susceptibility increased with an increase in niobium content. However, an improvement was observed when the Nb content became higher than 1.1 %. A low melting eutectic (FeCrNi)2Nb–γ was identified along γ dendrites by systematic study using SEM, TEM, EPMA and phase analysis, which was found to be the reason for the detrimental effect of Nb on solidification crack susceptibility.