Technology Development for Transition Metal-Rare Earth High-Performance Magnetic Materials
Semi-Annual interim technical rept. no. 2, 1 Jan-30 Jun 1971
GENERAL ELECTRIC CORPORATE RESEARCH AND DEVELOPMENT SCHENECTADY NY
Pagination or Media Count:
The angular dependence of the behavior of magnetization reversal discontinuities in single-particle samples was studied in an effort to obtain more information about the nature of the imperfections responsible for the discontinuities. It has been found possible to raise the coercive force of Co17Sm2, potentially a very high-performance permanent magnet material, by chemical treatment. Directionally solidified ingots of Co5Sm have been prepared for microscopic studies. While preferred growth transverse to the c-axis seems to predominate, one large grain near the beginning of the ingot showed a classic high-anisotropy transverse domain pattern. The minor impurities that might interfere with wet chemical analysis have been identified. It has been found that present processing techniques for sintered magnets do not substantially alter the composition of the starting material. Electron diffraction studies have identified the phases present in some sintered and heat-treated materials. Electron diffraction studies have identified the phases present in some sintered and heat-treated materials. Careful optimization of all processing procedures has resulted in a Co-Sm magnet with an energy product of 23.4 mGOe, Co-Pr-Sm magnets prepared from calcium-reduced oxide powders have shown an energy product of 25 mGOe. Measurements of Br and of magnetization at various fields emphasize the importance of alignment in influencing magnetic properties.
- Electrical and Electronic Equipment
- Metallurgy and Metallography
- Electricity and Magnetism