TiAl alloy was prepared using hot isostatic pressing process and the fully lamellar microstructure was
achieved via heat treatment. Then the diffusion bonding of TiAl and TC4 was invetigated. By the analysis of the microstructure,
mechanical property and fracture surface,it is found that TiAl alloy and TC4 alloy can be jointed well under
the conditions of 915℃ /80 MPa/1 h, and the joint achieves metallurgical combination. The joint part appears both
TiAl lamellar and TC4 rolling stripe. Strength of some joints exceeds the TiAl substrate. At room temperature,400℃
and 500℃,the joint tensile strength reaches 91. 77%,95. 27% and 99. 21% of the TiAl substrate,respectively.