Hot deformation behavior and processing map of a nickel-base superalloy GH4169

The hot deformation behaviors of the nickel-base superalloy GH4169 have been studied by isothermal constant true strain rate compression testing at 950 °C-1150 °C, 0.01s^-1-10s^-1 and the height reduction 50%. The processing maps of GH4169 alloy have been constructed at different strains on the basis of testing data using a dynamic materials modeling. The maps exhibited two domains: the first at 950 °C - 1100 °C and strain rate higher than 0.1s^-1, with a peak efficiency of power dissipation of 0.1, and the second at 950 °C-1100 °C and strain rate lower than 1s^-1, with a peak efficiency of power dissipation of 0.4 and the strain rate of 0.01s^-1. On the basis of microstructure observations, the first exhibits adiabatic shear bands, which called instability domain, the second represents fine recrystallized grain structures, which called stability domain. The optimal hot-working parameters are at 1050 °C, 0.01s^-1.