Factors Controlling Weld Toughness - The Present Position Part 1 Heat-affected Zones

TWI Industrial Member Report Summary 11/1976

By R E Dolby

Background

Current knowledge on metallurgical and arc welding procedural factors which control the toughness of heat-affected zones (HAZs) is reviewed. The Paper covers as-welded and postweld heat treated structures, together with transformed and subcritical HAZ embrittlement, and deals with C-Mn, C-Mn micro-alloyed, and low alloy steels. Particular attention is drawn to the need to distinguish between the various mechanisms of fracture initiation since the controlling metallurgical factors are different. A summary lists useful control measures for improving HAZ toughness.