Influence of homogenization degree on microstructure and mechanical properties for a novel wrought superalloy

Abstract

Abstract The present work aims at investigating the impact of homogenization time on microstructure and mechanical properties of a Ni-based superalloy GH4151 during hot deformation. The results showed that dense dendrite structure remained after homogenization at 1200°C for 5 h, which was similar to as-cast microstructure. Higher flow stress and cracking in 5 h-homogenized material is attributed to the integral deformation of microstructure with greater resistance and less recrystallization. Furthermore, the decrease in dense dendrite structure with increasing homogenization time helped to promote dynamic recrystallization (DRX) during deformation at 1200°C for 12h and 36 h due to increasing nucleation position. When the homogenization time increased to 60h, increase of grain size makes dislocation gather within grain and resistance increase.