Texture Evolution and Dislocation Behavior in a Nickel Based Superalloy during Hot Compression

Texture evolution and dislocation behavior of Ni-based superalloys at various temperatures and strain rate of 1 s(-1) are studied using electron backscatter diffraction (EBSD) technique and transmission electron microscope (TEM). It can be concluded that no significant texture is formed at high deformation temperature, especially for the occurrence of completed dynamic recrystallization (DRX). In addition, texture weakening is easy to realize by conducting DRX process on the Ni-based superalloys, whereas a slight strengthening is observed during grain growth. Based on the TEM images, the original grain boundary with high orientation gradient at low temperature provides an excellent position for DRX nuclei, which is strongly related with the dislocation motion. Moreover, it is concluded that the dislocation behavior plays a significant role in the plastic deformation of the Ni-based superalloys. Herein, theoretical guidance for the application of nickel-based superalloys and furthermore enhancement of their plastic deformation properties is provided.