Experimental study on Friction Stir Welding of copper metals

This study aimed to experimentally explore the thermal history of a workpiece undergoing Friction Stir Welding (FSW) involving butt joining with pure copper C11000. In the FSW experiments, K-type thermocouples were used to record the temperature history at different locations on workpiece. This data, combined with the preheating temperature, tool rotation speeds and tool moving speeds allowed parameters for a successful weld to be determined. Vickers hardness tests were conducted on the welds to evaluate the hardness distributions in the thermal–mechanical affected zone, heat affected zone and the base metal. Tensile tests were also carried out, and the tensile strength of the welded product was compared to that of the base metal. The appropriate temperatures for a successful FSW process were found to be between 460 °C and 530 °C. These experimental results and the process control of temperature histories can offer useful knowledge for a FSW based process of copper butt joining.