Irreversible losses of magnetisation in Fe-Nd-B type magnets

Irreversible losses of magnetisation for magnets, based on Fe-Nd -B alloys processed by melt spinning, HDDR, and sintering and on Fe-Nd-C-B ingot material, have been evaluated. Magnets having the same intrinsic properties and coercivity but different compositions and processed by different routes exhibit the same losses. Thus, optimization of the alloy composition, phase constitution and microstructure of the magnets, leading to high coercivity, appears to be crucial for minimisation of the irreversible losses of magnetisation. (orig.)