Modelling of a Stud Arc Welding Joint for Temperature Field, Microstructure Evolution and Residual Stress

This paper presents a modelling study and analysis performed on a stud welding including thermal, microstructure and stress calculation. The main concern of this work is toward controlling undesirable residual stresses and the evolution of material properties, as well as the chance of estimating cracks especially with regard to future services of structures. Historically, prediction of welding features is being pursued by welding engineers to enable them for optimal design and mitigation of adverse effects. Stud welding is among the welding processes that are not often addressed by means of modelling and associated activities to develop a comprehensive valid prediction. The aim of this research is to present a modelling practice for a stud weld joint to capture the transient thermal profile, consequent evolution of microstructural phase fractions, and stress calculation using a thermomechanical model based on FE methods (SYSWELD package). The material properties are fed into the model as temperature dependent. The microstructure model is based on t_8/5 cooling trajectory on CCT diagram that captures transformation from Austenite phase, and the residual stress calculation is compared to experimental measurement for the sake of validation.