Heat Production Simulation and Heat-force Couple Analysis of Fsw Pin

Article history: Received 2.10.2012 Received in revised form 30.1.2013 Accepted 1.3.2013 Heat production of friction stir welding (FSW) is a fundamental phenomenon that affects the welding quality. Early studies have been focused on investigating and understanding the heat production and temperature distribution of the welding plate. However, very few studies have been done to analyze the stress of the welding pin with reference to heat-force coupling, which is of great significance for the welding pin design. Therefore, this paper sets out to analyze the heatforce coupling effect of the welding pin. Firstly, considering the variation of heat conduction coefficient at different temperatures, the temperature distribution of both aluminum alloy 2A12 and copper plate were calculated for the FSW process. The temperature distribution results are then used to analyze the heat-force coupling of FSW pin referring to the cross force and axial pressure on the welding pin. The cross force and axial pressure are determined by the softened base metal which has different mechanical properties at different temperatures. The results show that the peak value of stress is at the boundary between the shoulder and pin. The pin is liable to break at peak stress, and hence more attention should be paid to welding tool design.