Effect of intercritical reheating during welding on the HAZ microstructure and toughness in a C-Mn-Nb-Al steel

TWI Industrial Member Report Summary 352/1987

By D J Sparkes

Background

Data comparing reheated regions of the HAZ are scarce, primarily because of difficulties in testing small regions of microstructure from actual welds. The present work employed thermally simulated specimens, reproducing a multipass submerged-arc weld at 3.5 H/mm in 50mm steel, to examine the microstructural effects of an intercritical thermal cycle on the coarse grained HAZ, and related these to Charpy and CTOD toughness.