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Pr-Fe-B die-upset magnets exhibited a lower remanence and a higher coercivity than analogous Nd-Fe-B magnets, with the microstructure of both magnets exhibiting similarities. Enhanced magnetic domain wall pinning and increased coercivity in Pr-Fe-B magnets was due to the thick intergranular phase. Hot-worked Pr2Fe14B magnets were obtained from melt-spun ribbons.

Die upsetting melt-spun ribbons of hot-pressed Pr-Co and Sm-Co pressure alloys produce the magnetically anisotropic PrCo5 type of magnets. Magnetic coercivity improves on low-level carbon addition to the alloys. Whereas increased carbon addition maximizes coercivity and drastically reduces magnetic remanence, PrCo5 type magnets have a higher saturation magnetization phase and substituting Sm for Pr and Fe for Co which would greatly improve the magnet's coercivity and remanence.

The use of high-remanence rapidly solidified Nd-Fe-B alloys as a starting material for die-upset magnets was investigated. The results showed that remanence increased along with the die-upset (DU) level and reached a maximum of 13.5 kG at 70% DU for ternary Nd-Fe-B magnets. Nonuniform deformation also had a detrimental effect on remanence. The decreased coercivity can be offset by heat treatments, dysprosium substitutions and low-level additives.

Differential scanning calorimetric estimations of the Curie temperatures of cobalt and iron diffusion in die-upset Nd-Fe-Co-B-magnets from metal-spun ribbons reveal a marked diffusion between ribbons that cause microstructure alteration and the deformation of the rigid 2-14-1 magnet. Cobalt diffuses across ribbons during hot working to rearrange the transition metal accumulation over the magnet. Homogenization of the metal composition is, however, not thorough.