Effect of reheating on microstructure and toughness of C–Mn weld metal

Abstract

AbstractSamples of C–Mn weld metal have been reheated to maximum temperatures of 900 and 1250°C, using an induction heating technique, and the resultant changes in microstructure and mechanical properties have been assessed. A model is proposed for brittle failure in this weld metal involving initial plasticity in grain boundary ferrite and crack initiation at nonmetallic inclusions. Variations between the brittle fracture susceptibilities of as-welded and reheated materials, and the scatter in brittle toughness results, can both be qualitatively understood in terms of the model.