Tensile and microstructural behavior of gas-tungsten-arc-welded electrolytic tough pitch copper joints

Electrolytic tough pitch (ETP) copper is extensively used in the manufacturing of electrical machines and automobiles. Compared with other pure coppers, ETP copper has lower weldability. Therefore, this study analyzes the weldability of ETP copper using the gas tungsten arc welding (GTAW) process. GTAW can be performed using constant-current (CC) and pulsed-current (PC) modes. Consequently, the properties of the joints fabricated using both modes are compared and analyzed in this study. The results show that the joint efficiencies of GTAW-CC and GTAW-PC joints are 81 and 89%, respectively. The optimal heat input and pulsating action in PC mode produce refined grains in the weld zone and heat-affected zone, resulting in a higher joint efficiency.