POWER AND THERMAL TECHNOLOGIES FOR AIR AND SPACE - SCIENTIFIC RESEARCH PROGRAM Delivery Order 0015: High Performance Permanent Magnets

摘要

Advanced permanent magnetic materials are in high demand by the Air Force. Developing high-performance nanomagnetic materials was the focus of this program. Methods for making anisotropic bulk nanocomposite magnets of Nd-Fe- B/Fe-Co, as well as Sm-Co/Co-Fe, were investigated, through which we gained comprehensive understanding in developing advanced magnetic nanocomposites. Several key challenges were identified, which include limiting oxidation during synthesis of the nanopowders, uniformly dispersing the two phases, maintaining the two distinct phases during consolidation processes at a limited temperature, and aligning the nanograins within the composite structure. Some possible solutions to overcome these challenges are recommended. Techniques of characterizing magnetic materials were also researched in this program by using both experiments and computer modeling, and the image effect in closed-circuit magnetic measurement was reported for the very first time by our researchers. The program also resulted in five published papers.