Properties of Welded Copper Tubes Fabricated Via Friction crush Welding

The welding process is one of the fabrication processes in which tubes can be performed for structural purposes and transport liquids or gases. This study is focused on the manufacturing, characterization, and evaluation of mechanical properties of welded tubes made from oxygen-free copper (C1020) sheets using friction crush welding. The welded tubes were produced using different tool rotation speeds (1500, 1600, and 1700 rpm) and feed rates (130, 140, and 150 mm/min). The flanged edge height of 2.5 mm and 0.5 mm gap between the ends of the copper sheet was used. All examinations on welded tubes were achieved using different instruments such as optical microscopy, SEM, hardness, and tensile testers. The microstructure study showed good weld quality and good material flow between the two ends of the copper sheet in the weld zone. Moreover, the weld zone was not defective. The lowest hardness was identified in the crush zone due to the coarseness of the copper grains. The highest tensile strength of 105 MPa was obtained at the tool rotation speed of 1500 rpm and 130 mm/min feed rate. The results also showed that ductile fracture is the main source of failure.