TWI Industrial Member Report Summary 473/1993
By S D Smith and F J Blunt
Background
Previous work has shown that, in contrast to the HAZ situation, weld metal hydrogen cracking risk can increase at higher arc energy. This may stem from the resultant larger weld bead retaining a higher proportion of the original hydrogen on cooling to room temperature than with lower arc energy deposits.
A description is given of a finite element model to predict hydrogen diffusion and final hydrogen distributions in single and multipass CMn steel welds. The modelling procedure was applied to a single pass gapped bead-on-plate specimen (G-BOP) and to a seven pass (5kJ/mm) weld and a 14 pass (3kJ/mm) weld.