Fe-Cr-Co magnets

This paper reviews the recent developments of Fe-Cr-Co permanent magnet alloys. The Fe-Cr-Co alloys offer magnetic properties comparable to those of Alnico alloys, but with a distinct advantage of being ductile and containing less cobalt. Considerable effort has been expended in understanding the relationship between the alloy microstructure, chemistry, phase relationship, and permanent magnet properties as well as in processing development for improved coercivity and energy products. In this paper, various aspects of the processing, structure, origin of coercivity, magnet properties, and applications of the Fe-Cr-Co alloys will be discussed.