Investigation for the Novel Formation of High Energy Product Fe Compacts.

摘要

Two novel approaches were examined for the production of economical permanent magnets containing little or no critical materials. The first approach was to induce a strong surface anisotropy or spin pinning on Fe particles by coating them with suitable materials. Another aspect of this approach was to gain a deeper understanding of the mechanism of spin pinning. The principal positive result in this case was the establishment, by neutron diffraction, that spin pinning does occur on ferrite particles when coated with oleic acid. The second approach was to prepare rapidly quenched precursor particles of various alloys and then anneal them to produce optimum magnetic properties. One result of this work was a demonstration of how different degrees of chemical short range order resulting from different quench rates yield different crystallization behavior, thus affording a measure of control over magnetic properties. Another important result of this phase was that very promising properties were produced in Mn-Al-C particles. (Author)