Key points are not available for this paper at this time.
We report the properties of a new class of high-performance permanent magnets prepared from Nd-Fe-B and Pr-Fe-B alloys. Magnetic hardening is achieved by rapid solidification. Energy products of these isotropic materials can exceed 14 MGOe with intrinsic coercivities of ∼15 kOe. X-ray and microstructural analyses indicate that the alloys exhibiting optimum characteristics are comprised of roughly spherical crystallites, strongly suggesting that the coercivity mechanism is of the single-domain particle type. The crystallites are composed of an equilibrium R-Fe-B intermetallic phase having tetragonal symmetry, and the stability of this phase with respect to other rare earths and other metalloids has been investigated.
Croat et al. (Thu,) studied this question.