Abstract:
TC8 titanium alloy was subjected to room temperature quasi-static tensile tests at different strain rates (0.000 1, 0.001, 0.01 s
-1) and dynamic compression tests at different strain rates and temperatures on the Hopkinson pressure bar device. The quasi-static and dynamic mechanical properties of the alloy were studied. The test data was fitted to obtain the parameters and then J-C constitutive model was established. The constitutive model was verified by tests. The results show that the yield strength, tensile strength and maximum equivalent failure plastic strain of TC8 titanium alloy all increased with increasing strain rate in the quasi-static tensile tests. The yield strength and ultimate strength of the alloy increased with increasing strain rate in the room temperature dynamic compression test, exhibiting an obvious strain rate strengthening effect; the yield strength and ultimate strength decreased with increasing temperature, exhibiting a significant temperature softening effect. The true stress-true strain curve calculated by the fitted J-C constitutive equation was consistent with the test results, and the average relative error was 4.82%, indicating that the constitutive model could predict the dynamic mechanical properties of TC8 titanium alloy at high temperature.