We have investigated the microstructure of grain boundary diffusion processed Nd–Fe–B sintered magnets by high resolution scanning electron microscopy, high resolution transmission electron microscopy, and laser assisted atom probe to understand the mechanism of coercivity enhancement. After the vapor coating of Dy to the sintered magnets, the sample were annealed to let it diffuse in the sample through the grain boundary diffusion. The composition of the outer region of the [formula omitted] grains changed to [formula omitted] due to the substitution of Dy for Nd. Excess Nd ejected from the [formula omitted] grains led to the formation of continuous Nd-rich grain boundaries.
ASJC Scopus subject areas
- Physics and Astronomy(all)