High Temp High Energy Product Permanent Magnet Material

Permanent magnet materials with high energy product of (BH)max = 30 MGOe at 450°C are needed for advanced Air Force power and weapon systems. This required magnetic performance represents a 150% improvement over the best existing materials. Owing to the very high degree of difficulty, this objective is unlikely achievable if using any existing permanent magnets, such as conventional high temperature SmCo5, Sm2Co17, or nanocomposite Sm2Co17/Fe-Co because of various technical difficulties. New R2Co17 compounds are identified and will be used in the proposed STTR Phase I project to demonstrate the feasibility of synthesizing novel high temperature and high energy product permanent magnets. These compounds have high Curie temperatures of 910 - 930°C. Their saturation magnetization can reach 12 kG at 450°C. If they also possess high uniaxial magnetocrystalline anisotropy, or if high uniaxial magnetocrystalline anisotropy can be developed, then it will be possible to make nanocrystalline magnets based on these new compounds by allying inductive rapid hot compaction and subsequent hot deformation.