High Speed Friction Stir Welding: A Computational and Experimental Study

A three-dimensional numerical analysis of friction stir welding at high speed (HS-FSW) is presented here. The temperature distribution in the workpiece has been calculated for a number of processing conditions. The analysis adopts a thermal model based on the simple laws of friction. This model translates to having a moving heat source along the weld-line on the top surface of the workpieces. Results have been validated experimentally using an infrared camera as well as thermocouple measurements. By comparing actual welds performed on Aluminum 6061-T6 and the numerical predictions, it is observed that the appropriate range for the (maximum) surface temperatures for obtaining a sound weld is between 570°C and 530°C, and that these temperatures are achieved between spindle translation velocities of 125 mm/min and 250 mm/min, respectively.