Thermal activation analysis on strain rate dependence of high-temperature tensile properties in TiAl alloy

摘要

Tensile properties of a two-phaseγTi-47Al-1.5Cr-0.5Mn-2.8Nb alloy with a duplex microstructure were tested under strain rates ranging from 5×10{sup}(-5) to 5×10{sup}(-3) s{sup}(-1) at temperatures from 1123 K to 1273 K. It was found that there exists approximately linear relationship between the flow stresses and the logarithm of the strain rate at different temperatures. The strain rate dependence was analyzed by thermal activation theory, and dislocation climbing has been identified as the rate controlling mechanism.