Criteria for hot cracking evaluation in austenitic stainless steel welds using longitudinal varestraint and transvarestraint tests

The longitudinal varestraint test (LVT) and transvarestraint test (TVT) are widely used for assessment of weld metal cracking susceptibility. The TVT is preferred over the LVT for study of weld metal cracking. However, few reports exist that discuss the relative merits of the two tests for evaluating cracking susceptibility. This investigation was carried out to compare weldability assessments using the two tests and the relevant criteria for weldability evaluation. Several stainless steels solidifying in the austenitic and ferritic solidification modes were tested. The study shows that the LVT can be used for evaluation of fusion zone cracking through a maximum cracking distance criterion. This parameter correlated well with the maximum crack length in the TVT, traditionally used to derive the brittleness temperature range (BTR). The study further indicates that the total crack length can be related to the BTR by considering the area density of cracking.