Research progress on diffusion bonding technology and interface regulation of Ti/Al dissimilar metal

Titanium/aluminum composite components have advantages of lightweight, high strength, corrosion resistance and so on, which make them widely used in new energy vehicles, aerospace and other fields. However, there are large difference between physical properties of titanium and aluminum, and brittle intermetallic compounds such as TiAl₃ and TiAl are easily produced, which leads to performance degradation of titanium/aluminum dissimilar metal joints. In order to solve the above problems, based on advantages of diffusion bonding technology in dissimilar metal bonding, such as small deformation, no pollution and dense metallurgical bonding, application of diffusion bonding technology in titanium/aluminum dissimilar metal bonding was discussed in detail, as well as influence of welding parameters such as bonding temperature, holding time and pressure, post-welding heat treatment process and intermediate layer on welded joints. Microstructure and properties of titanium/aluminum joints controlled by process control and addition of intermediate layer were summarized. The results showed that combination of process control and suitable intermediate layer could minimize type of brittle intermetallic compounds and reduce thickness of intermetallic compounds. On this basis, development trend of titanium/aluminum dissimilar metal diffusion bonding was discussed.