Experimental investigation and finite element analysis of welding induced residual stresses

Abstract

Welding is one of the most important metal joining techniques due to its advantages in relation to speed and versatility. One of the unwanted effects of gas metal arc welding is residual stress, that arises due to the inherent temperature loadings and can lead to structural integrity or assembly problems. Experimental investigation of these effects is highly desirable but often costly, especially in large-scale construction such as shipbuilding. It is therefore of interest to exploit the potential of computational analysis techniques, such as finite element analysis, for the assessment of these effects. The use of finite element analysis in this context is however not straightforward, due to the complex nature of the problem. The work presented here deals with an experimentally validated modelling strategy applied to two weld joint configurations: butt and fillet welded plates. Simulation techniques are presented which are aimed at predicting residual stresses. These are validated against measurements carried out using the hole drilling method for residual stress determination. Results show a good qualitative and quantitative match in simulated and experimentally measured values, which back up the modelling techniques adopted

Thermal Stresses and Distortion Developed in Mild Steel DH36 Friction Stir-Welded Plates: An Experimental and Numerical Assessment

“…Develop and validate global thermo-elastoplastic numerical models. These models are based on previous research on DH36 mild steel fusion welding [17][18][19] and are adapted to take into account influences due to heat sinks, rigid clamping, plunge forces and material mass transportation associated with the friction stir welding process. 3.…”