Hot working characteristics of a high Nb containing TiAl alloy with ( γ+β ) microstructure

In this study, the hot working characteristics of a (3-solidifying gamma-TiAl alloy with (gamma+(3) microstructure were systematically investigated. The effects of temperature, strain rate, and deformation degree on microstructure evolution were examined. As temperature increased and strain rate decreased, the microstructure underwent complete dynamic recrystallization, necessitating a height reduction exceeding 40 %. Utilizing the compressive data, the constitutive equation was established through the strain iteration method. Furthermore, a hot processing map using this constitutive equation was generated, which exhibited high accuracy and could effectively predict microstructure. In the domain of high temperature and low strain rate, the majority of energy was directed towards promoting microstructure evolution, leading to a peak in power dissipation efficiency. Optimal hot working conditions for this alloy falls at temperatures ranging from 1273 K to 1473 K or higher, with a strain rate not exceeding 0.1 s- 1 .