摘要 |
A process for preparing novel sintered cobalt-rare earth intermetallic products which can be magnetized to form permanent magnets having stable improved magnetic properties. A cobalt-rare earth metal alloy is formed having a composition which at sintering temperature falls outside the composition covered by the single Co5R intermetallic phase on the rare earth richer side. The alloy contains a major amount of the Co5R intermetallic phase and a second solid CoR phase which is richer in rare earth metal content than the Co5R phase. The specific cobalt and rare earth metal content of the alloy is substantially the same as that desired in the sintered product. The alloy, in particulate form, is pressed into compacts and sintered to the desired density. The sintered product is comprised of a major amount of the Co5R solid intermetallic phase and up to about 35 percent by weight of the product of the second solid CoR intermetallic phase which is richer in rare earth metal content than the Co5R phase.
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