Date of this Version
United States Patent Application Publication LEWIS et al . Pub . No . : US 2018 / 0114614 A1
The invention provides rare earth - free permanent magnetic materials and methods of making them . The materials can be used to produce magnetic structures for use in a wide variety of commercial applications , such as motors , generators , and other electromechanical and electronic devices . Magnets fabricated using the materials can be substituted for magnets requiring rare earth elements that are costly and in limited supply . The invention provides two different types of magnetic materials . The first type is based on an iron - nickel alloy that is doped with one or more doping elements to promote the formation of L1 , crystal structure . The second type is a nanocomposite particle containing magnetically hard and soft phases that interact to form an exchange spring mag netic material . The hard phase contains Fe or FeCo , and the soft phase contains AlMnC .