TWI Industrial Member Report Summary 376/1988
By D J Abson
This study represents the second phase of a programme investigating butt welds produced using semi-automatic continuous wire processes with consumables suitable for welding BS 4360:1986 Grade 50EE and similar structural steels. Such consumables are of interest because their higher duty cycle gives the potential for a higher deposition rate than that achieved with MMA electrodes. Five panels, which were welded vertically-up, were investigated previously in the as-welded condition; here, portions of these same panels have been studied after post-weld heat treatment (PWHT). The consumables employed were a 2mm self-shielded flux-cored wire, and various 1.2mm wires which were welded with an Al-20%CO2 shielding gas.
As in the previous phase of the programme, the hardness, tensile properties and Charpy toughness were investigated in the first (major) side root region and in the second side fill region. The critical crack tip opening diplacement (CTOD) was also determined. Fractographic and metallographic studies were carried out, in order to investigate the causes of the observed behaviour.