Cyclic Stress-Strain Response and Dislocation Configuration of a Beta Phase Containing TiAl Alloy during Isothermal Fatigue Tests under Different Strain Rate

Abstract

A beta phase containing titanium aluminum compound was prepared. Isothermal Fatigue(IF) were subjected at 650 °C at three strain rates, such as 6.67×10-3 s-1, 6.67×10-4 s-1, 6.67×10-5 s-1 to determine the effect of strain rate on cyclic stress-strain response (CSSR) of TiAl alloy during IF tests. The curves of cyclic stress-strain response were discussed and dislocations configuration were also observed by TEM. The results show that strain rates have an apparent effect on CSSR of TiAl alloy during IF tests and CSSR was identified that it had a close relationship with dislocation configuration and deformation twin.