Review on thermal, thermomechanical and thermal stress distribution during friction stir welding

Thermal has significant effects on the metal structure during welding process; it plays vital roles in rearranging molecular structure of the metal being welded. It is of great importance to have the knowledge of thermal, temperature, thermo-mechanical and heat distribution on the workpiece in friction stir welding as this will help in designing process and the model parameters for welding application in the following welded joints, edge butt, lap, square butt, T lap, fillet, multiple lap etc. The physics of heat generation must be explored in order to understand the workability of friction stir welding (FSW). The FSW process begun with initial friction of mechanical that took place between the tool and the welded surface resulting in the generation of heat. Since the discovery of Friction Stir Welding (FSW) in 1991, many researchers have done tremendous investigations into the process and many experimental, theoretical, numerical, empirical, computational and analytical methods have been carried out in order to analyse and optimize FSW and to understand the complex mechanism in friction stir welding at the same time to deal with effects of various parameters relating to thermal profile during the process of FSW.