Hot workability integrating processing and activation energy maps of Inconel 740 superalloy

Abstract

The optimum hot working window with full dynamic recrystallization microstructure for Inconel 740 superalloy was established by integrating the activation energy map with the hot processing map. The activation energy map and the hot processing map were obtained respectively to characterizing the hot workability based on the isothermal compression tests at various temperatures and strain rates. Hot deformation characteristics of Inconel 740 superalloy was investigated by analyzing the microstructure evolution. The results show that the flow instability is significantly dependent on the high activation energy. Whereas, the good hot workability is attributed to the low activation energy, in which case the original microstructure is replaced by the fine and equiaxed recrystallization grains.