Simulation on Ti-based filler and vacuum brazing for TA15 alloy

A model was established for four-element material with HCP structure by EET. The filler of TiZrCuNi was analyzed by the model. It was found that Ni element is beneficial for the strength of the filler but Cu element is beneficial for the ductility of the filler. It showed that controlling the amount of Cu and Ni with the proper distribution of them was important. Compared with the filler Ti-13Zr-22Cu-9Ni wt%, the designed Ti-(10~11)Zr-(10~12)Cu-(9~10)Ni wt% with lowering the amount of Cu and Ni to 19 wt% also has strong strength and good ductility. The TA15 joint by vacuum brazing was conducted with the designed filler metal—Ti-(10~11)Zr-(10~12)Cu-(9~10)Ni wt%. The interface without IMC was achieved and the homogeneous Widmanstatten microstructure was attributed to the high strength of the joints. And all the fracture occurred in the base.