A review on laser beam welding of copper alloys

With exponentially increasing copper alloys consumption globally, the automatization, high efficiency, and quality improvement of the copper joining process become inevitable in modern industrial production. In this context, laser welding presents a particular suitability for joining of copper alloys because of its high precision, high-energy concentration, and rapid processing potentials. Studies have shown that laser welding of copper has two principal challenges. Namely, the high laser power required due to the low laser beam absorptivity and high thermal conductivity of copper, and the low process stability. Interestingly, with the recent laser technology improvements, the tremendous laser power required will eventually be solved. Although some achievements were obtained in previous studies, the problem of spattering and high porosity associated with low process stability still exist. In this review, the effect of the most significant laser welding processing parameters on the joint's performances were systematically examined; the microstructure, mechanical, and electrical properties and metallurgical defects of copper laser welds were discussed. Furthermore, laser welding of copper to other metals particularly copper to steel and copper to aluminum dissimilar alloys in terms of structure and properties relationships were also discussed.