Numerical investigations on the influence of the HAZ on the resistance of welded HSS T‐joints

Welding induces heat, which can cause high‐strength steels (HSS) to soften in the heat‐affected zone (HAZ). To analyse the effects of this softening on the strength of welded joints, experimental and numerical investigations were conducted on single‐sided welded T‐joints as part of the AiF‐FOSTA research project P1453. While the experimental investigations of the study covered specimen preparation, manufacture, experimental execution and evaluation of load‐bearing capacity tests, the focus of this article is on structural–mechanical investigations to further examine the behaviour and resistance of T‐joints with HAZ failure. Based on the experimental results, geometrically and materially non‐linear finite element models were developed to analyse the structural behaviour of single‐sided welded T‐joints. The investigations focused on simulating different tensile strength mismatching ratios between the base material, weld metal, and HAZ. In conjunction with the experimental investigations, the structural–mechanical investigations presented here form a comprehensive data basis for developing a semi‐analytical model to determine the load‐bearing capacity of welded HSS joints with HAZ failure.