Effect of dilution ratio in hard facing weld metal on solidification cracking susceptibility

This work aims to study the influence of dilution ratio between a hard facing wire MSG 6-GZ-60 and ER70S-6 on solidification cracking susceptibility. The combination of MSG 6-GZ-60 and ER70S-6 weld metal were built-up on a carbon steel plate as the ratio of 50%, 75%, 90% and 100%. Solidification cracking susceptibility test was carried out by Trans-Varestraint Test (TVT). Such the TVT test, solidification cracking of weld metal specimens was stimulated through immediately bending during GTAW welding. Bending strain levels of 4.8% were employed. Maximum crack length and number of cracks were investigated. As a result, it was found that increasing the dilution of ER70S-6 weld metal butter layer could decrease maximum crack length. In contrast, increasing MSG 6-GZ-60 weld metal dilution promoted a crack length. As for cracking distribution, the results presented increasing ER70S-6 weld metal dilution was able to conduct significantly more cracking distribution. This will be useful to the appropriate dilution ratio for avoiding cracking in the hard facing welding.