Misorientation statistics across hot-deformed Nd2Fe14B permanent magnet boundaries and the potential correlation with magnetic properties

Abstract

In this study, planar electron backscatter diffraction data of hot-deformed (HD) Nd₂Fe₁₄B magnets were analyzed to investigate the misorientation relationships on the grain boundary plane. The potential correlation between the misorientation angles of Nd₂Fe₁₄B/Nd₂Fe₁₄B grain boundaries (Nd/Nd boundaries) and Nd₂Fe₁₄B/Nd-rich phase boundaries (Nd/Nr boundaries) was explored, along with their impact on the properties of the magnets. The characteristics of the grain boundary plane distribution of specific preferred misorientation angles were also investigated. The results revealed that the Nd/Nd boundaries exhibited preferred misorientation angles of 45° and 56°, whereas the Nd/Nr boundaries showed angles of 45° and 62°. The 45° grain boundary plane preferred the (001) orientation, and the 56° grain boundary plane favored the (122) orientation, and the 62° grain boundary plane preferred the (010) orientation. By integrating materials science and computational science, this study improves the understanding of the interface structure and properties of HD Nd–Fe–B magnets.