Conceptual model for stress and strain development during welding with trailing heat sink

Abstract

It has been proven by several research groups that welding with a trailing heat sink can reduce the buckling distortion of welded thin sheet. However, the transient mechanical behaviour during welding with a trailing heat sink was never fully understood. This paper presents a conceptual model that is capable of explaining both the longitudinal plastic strain and the longitudinal stress development during welding with an active cooling source. The model is based on an existing three bar model for stress and strain development during conventional welding. Comparison with three-dimensional finite element calculations shows that the model gives qualitatively realistic results. The model provides insight into the relevant mechanisms involved in stress development during welding with a trailing heat sink, which is essential for determining the optimum cooling source parameters.

Keywords:

• WELDING
• RESIDUAL STRESS
• DEFORMATION
• BUCKLING
• LOW STRESS NO DISTORTION WELDING
• ACTIVE COOLING
• MODELLING