Flow Behavior and Numerical Simulation of Spray-Formed FGH95 Superalloy Under Hot Compression

The flow behavior of spray-formed FGH95 superalloy (similar to Rene 95) was investigated at temperatures ranging from 1050 to 1140 °C and strain rate ranging from 0. 01 to 10 s−1. At a given temperature and strain rate, flow stress increases quickly with increasing strain and then reaches a peak, then gradual decreases until high strain, and dynamic softening is observed. Utilizing the hyperbolic sine function and introducing the strain with nonlinear fitting, the revised constitutive equations incorporating the effects of temperature, strain rate and strain for high temperature flow stress prediction of superalloy were established. The revised constitutive equations were implanted into finite element software by second development to simulate the hot compression process successfully, and the effective stress and load stroke curves obtained by numerical simulation are good agreement with the experimental results.