Abstract:60NiTi alloy has a series of excellent properties such as high strength and good wear resistance, but it is difficult to thermal forming. Therefore, its wide application in the industrial field is greatly limited. In order to determine the optimal hot working process of 60NiTi alloy, the hot deformation behavior of as-cast 60NiTi alloy was studied and the constitutive equation of high temperature deformation was established in this work. The temperature of hot deformation ranges from 750℃ to 1050℃ and the deformation rate ranges from 0.01s-1 to 1s-1. The result shows that the dynamic recrystallization of 60NiTi alloy occurred at 1000℃ and 0.01s-1 rate. When the storage energy in the crystal was high, the precipitation of Ni3Ti phase was inhibited but Ni4Ti3 phase was promoted. In order to achieve the best thermal forming performance, 60NiTi alloy should be processed at high temperature (1050℃) with a large deformation rate (1s-1).
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