Abstract:The effect of near isothermal forging and gradient heat treatment on the micro-hardness distribution, the trend of elements diffusion, the microstructure and tensile property have been investigated for the welding Ti-24Al-15Nb-1.5Mo/TC11 dual alloys joint. The results show that the joint can be strengthened through near isothermal forging and gradient heat treatment. During heat working, the martensite a’ phase and a2 phase in fusion zone of joint are breaken up into a balance microstructure consisting of a (a2) phase + b phase. The Widmanstatten structure changes into the basket weave structure in the alloy TC11 heat-affected zone of joint. In addition, the joint has excellent high temperature properties after near isothermal deformation and gradient heat treatment (sb is 840 MPa, d is 18.5%, and y is 65%)