Modelling thermal processes in welding

Distortion and residual stress are driven by the thermal gradients generated by the moving heat source. Heat energy enters the workpiece through the fusion zone primarily and procedures are provided to model heat input as a lumped source, including the effects of weld filler deposition and losses due to convection and radiation. Alternative three-dimensional and two-dimensional thermal models are given. Stiffener fillet welding involves more conduction routes and a double-sided fillet stiffener weld is treated. Methods to determine welding thermal efficiency are given, with values for different processes. The characteristics of thermal cutting are discussed.