Finite element simulation and experimental verification on hot extrusion of a novel nickel-base P/M superalloy

The finite element method was used to optimize the hot extrusion process of a novel nickel-based powder metallurgy superalloy in this paper, the influences of finite element parameters on hot extrusion were analyzed and discussed, and the reliability of finite element simulation was verified by extrusion experiment. The results show that, the initial temperature of billet has a significant effect on the stress and temperature during hot extrusion process, but has no obvious influence on the strain rate and strain. The speed of extrusion stem is an important parameter to control the stress and strain rate. The uniformity of stress, strain rate, strain, and temperature can be greatly improved by using smaller die angles (< 45.0°), which can effectively avoid the cracking of extrusion bar and ensure the uniformity of microstructures. The main hot extrusion parameters are recommended as following: the initial temperature of billet is 1100℃, the speed of extrusion ram is 40 mm·s^-1, and the die angle is 40.0°. It is proved that the parameters applied to the hot extrusion experiment based on the finite element analysis are accurate and reasonable.