Microstructural evolution in forged Ti Alloy TC11 during superplastic deformation

摘要

Experiments were conducted under different conditions of superplastic deformation (SPD) at constant temperatures, in order to investigate the mechanism of SPD for forged TC11, an atypical superplastic titanium alloy. It has been known that for such an alloy, which possesses positionally distributed original microstructure and nearly equiaxed grains, demonstrates some features during SPD: the microstructure changes finally into homogeneous microstructure and the state of "dynamic equilibrium" can be achieved. During this process, "grain group" movement was shown to exist. Moreover, the TEM results show that subgrains might contribute a lot to SPD for TC11.