Thermal cycle method’s applicable conditions for predicting residual stresses in low-strength steel weldments induced by arc welding

Abstract

The present study purposes to systematically investigate the viability of the fast computation method “thermal cycle method (TCM)” for simulating welding residual stresses (WRS) in transforming and non-transforming low-strength steel weldments under various restraint conditions. Both experimental and finite element analysis were performed. Comparison of the predicted WRS with the measurements reveals that TCM is completely not suitable to assess WRS in the transforming low-strength steel weldments with low restraint degrees in numerical simulation. Nevertheless, that is feasible overall when the constraint degree is high, although this method reduces the accuracy of the calculated longitudinal residual stress to some extent in base material (BM). For non-transforming single-phase low-strength steels, no matter how much the restraint degree of the weldment is, it is trustworthy using TCM instead of the commonly applied moving heat source to calculate WRS for reducing the computational time. Based on the current work, the application conditions of TCM for the assessment of WRS in the low-strength steels induced by arc welding are systematically clarified.