Rare Earth Permanent Magnets Based on the Metastable SmCo13 Phase for XIPSs

The objective of this effort is to develop high performance rare earth permanent magnets that can survive temperatures as high as 500?C for Xenon ion propulsion systems applications. Rare earth permanent magnets based on the SmCo13 phase were shown to possess good magnetic performance at temperatures as high as 500?C. We propose to initiate the development and commercialization of new rare earth permanent magnets of composition based on the 1:13 SmCo13 phase of the general form: (Sm(1-t-u-w)GdtEruHow)(Co(1-v-x-y)FevCuxZry)13. TASK 1 will investigate 1:13 magnet compositions using SEM-WDS to determine the exact composition of the (Sm,Er,Ho)TM13 phase previously observed. TASK 2 will prepare single-phased Sm(Co,Fe,Cu,Zr)13 alloys. TASK 3 will determine basic magnetic parameters of the 1:13 compounds such as magnetization, Curie temperature, magneto-crystalline anisotropy constant, magnetic anisotropy field, and the crystal structure. TASK 4 will perform preliminary investigations of high temperature coatings that eliminate or provide minimal thermal degradation for long-term high temperature exposure. Permanent magnets that maintain acceptable performance at high temperatures will permit higher thrust to weight ratios, and reduce the weight of cooling systems required to maintain magnet performance. This weight savings will translate into increased payload capability.