Patent ID: 11875934
Assignee: REGENTS OF THE UNIVERSITY OF MINNESOTA
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  C | IPC C  H

Claim 0:
1. A permanent magnet comprising the iron-nitride material obtained by a method comprising:
preparing a raw material comprising iron;
carrying out a microstructure build-up by annealing the prepared raw material at an elevated temperature and subsequently quenching the prepared raw material to produce a microstructure build-up material; and
nitriding the microstructure build-up material to produce a nitrided material and subsequently quenching the nitrided material to a martensitic transformation temperature, stress annealing, and magnetic field annealing;
wherein the microstructure of nitrided material is a martensite morphology with plate-like shape;
wherein the material has a polycrystalline microstructure including a plurality of elongated, plate-like crystallographic grains with grain boundaries, comprising an α″-Fe16N2 phase;
wherein the peak height of the Fe16N2 (220) x-ray diffraction peak is greater than the peak height of the Fe16N2 (202) x-ray diffraction peak of the material.