3D Multi-pass finite element welding modelling of butt-welded plate specimen

Abstract

A multi-pass welding of a thin rectangular (dog-bone shaped) butt joint plate is numerically simulated as a coupled thermo-mechanical transient problem. The simulation uses an “element-birth” technique to simplify the complexity of the problem. The paper discusses the challenges of the simulation of a multi-pass weld problem and the utility of the results for practical applications. The final solution shows crucial stress distributions in a challenging geometry where large thermal transients and gradients are created by the welding procedure. The results also indicate the plastic yielding of the weld-joint after extensive cooling of the joined plate. The displacements from the results can be used to estimate the extent of distortions qualitatively. Despite minimal resources (2 CPUs on a standard Intel desktop architecture and 2 GB RAM over duration of 4 days) the procedure is able to provide adequate details in predicting residual stresses for multi-pass welded components.