Research State-of-the-Art on Controlling Ti-Al Intermetallic Compound (IMC) Formation During the Laser Beam Welding (LBW) of Ti and Al Alloys

Ti-Al dissimilar metal composite structures have the advantages of the low density of Al alloys and the high strength and good corrosion resistance of Ti alloys, thereby reducing structural weight and saving energy in manufacturing. The joining of Ti and Al alloys, however, is faced with great difficulty due to the differences in physical and chemical properties between the two materials. Brittle intermetallic compound (IMC) formation in the welds decrease the ductility and formed cracks in the Ti/Al joints. The research results show that the welding with filler can reduce the content of brittle TiAl3 phase in the interface compared with the unfilled welding process. This paper introduced the research status of Ti and Al alloy welding structures and the mechanism of controlling Ti-Al IMCs by different welding structure in laser beam welding (LBW). The research situation and the control methods of brittle Ti-Al IMCs are discussed.