Isothermal forging process design for spray-formed FGH95 superalloy turbine disk based on numerical simulation

Based on the experimental data from hot compression tests on Gleeble 1500 thermal simulator, the revised constitutive equations of spray-formed FGH95 superalloy considering the effect of strain on the material constants were established. The average absolute relative error (AARE) was employed to verify the validity of the constitutive equation, and the value of AARE is 3.85 %. Subsequently, the revised constitutive equations were successfully used to simulate and analyze the deformation behavior, stress distribution, forming loads and temperature distribution in both dies and billet during the isothermal forging process of turbine disk of large dimension (about 400 mm in diameter) by the means of finite element method (FEM). Moreover, the optimum process parameters are 1,120 A degrees C of forging temperature and 0.01 s(-1) of strain rate for the spray-formed FGH95 superalloy turbine disk.