A critical review of microstructure and mechanical properties of laser welded similar and dissimilar titanium alloy joints

Recently, the automotive and aerospace industries have witnessed increased usage of titanium alloys. Nevertheless, the fabrication of titanium parts using conventional fabrication techniques is challenging owing to their low thermal conductivity, high affinity for oxygen, high melting temperature, high strength, and poor machinability. Advancements in welding technologies have resulted in the development of safe, efficient, and cost-effective joining techniques capable of overcoming the aforementioned challenges and enhancing titanium weld quality. The traditional approach and equipment used for welding aluminium and stainless steel had been utilized for joining titanium and its alloys but with limited success compared to the laser welding technique. Laser welding is the preferred method of welding because of its excellent qualities and great reliability, particularly for titanium alloy connections, which are frequently used in aerospace and aircraft structures. This work reviews recent works and progress recorded in laser welding of similar and dissimilar titanium alloy joints under varying processing parameters. The essential findings highlighting the impact of laser processing variables on the evolution of microstructural features, mechanical characteristics, and variations in corrosion resistance associated with laser-welded titanium joints in different environments are extensively highlighted. Finally, insightful information and prospects on laser welding of similar and dissimilar titanium alloy joints are provided.