Solidification and transformation behaviour of austenitic stainless steel weld metals solidified as primary austenite: study of solidification and subsequent transformation of Cr-Ni stainless steel weld metals (1st report)

摘要

This paper describes an investigation of the solidification and subsequent transformation behaviour of two Fe-Cr-Ni stainless steel weld metals using the liquid-tin quenching method. One weld metal solidifies in the austenitic single phasesolidification mode (A mode) and the other in the austenitic-ferritic solidification mode (AF mode). In the A mode solidified weld metal, both Cr and Ni are enriched in the interdendritic regions during solidification, where the degree of enrichment of Cr is greater than that of Ni. The microstructural characteristics established during solidification, the concentration profiles of the elements, and the crystallographic orientations are similarly observed at room temperature. During AF mode solidification, globular ferrite is formed through the eutectic reaction at the cell boundaries. The 100{sub}γ direction of the primary austenite is found to be parallel to the 100δ direction of the eutectic ferrite, and both phases are found to grow in thepreferential growth directions.