Discontinuous yielding behavior and microstructure evolution during hot deformation of TC11 alloy

Discontinuous yielding behavior of TC11 alloy was found during hot compression tests at temperatures of 1000-1050 °C and the strain rate of 10 s−1. The flow stress showed a rapid drop and subsequent oscillation after peak stress before true strain of 0.15. It was proved to be the result of the stress induced phase transformation (α→β), which introduced softening effect for the generation of new β phase. Moreover, the magnitude of the stress drop increased with the increasing of the fraction of stress induced phase transformation. In addition, these newly generated β phase were further deformed by subsequent compression strain. As a result, the phase transformation of β→α″ was found in final quenched microstructures.