Study of Dissimilar Laser Welding: A Review

Laser beam welding (LBW) is an advanced welding technique having high-power density and a small focal spot that has been widely applied to join multiple metal parts by utilizing the heat generated from the focusing of amplified coherent light photons known as LASER. LBW is extensively used to join dissimilar metals and alloys in offshore structures, pipelines, aerospace, shipbuilding, power plants, and tool and die industries because of advantages like controlled heat dissipation, smaller weld bead formation and minimal heat affected zone (HAZ). However, the dissimilar metal joining process tends to form a brittle intermetallic compound (IMC), leading to solidification cracking in the weld bead, thereby reducing the dissimilar joint strength and making the process of joining dissimilar metals a challenging task. The current work explores the basic phenomenon in different weld zones and their influence on dissimilar laser-welded joints. An overview of the dissimilar laser welding of materials such as aluminium, titanium, and stainless steel, along with the development of major techniques to reduce IMC formation, has been presented.