| 摘要 |
PURPOSE:To manufacture an inexpensive permanent magnet having sufficient coercive force and high efficiency, by subjecting an alloy containing rare-earth elements, transition metals, and boron as principal components to melting, to cooling at a specific cooling rate, and then to heat treatment. CONSTITUTION:An alloy containing rare-earth elements (including Y), transition metals, and boron as principal components is melted, heated at 10<-1>-10<6> deg.C/sec cooling rate by a double roll method, etc., and then heat-treated at >=250 deg.C to undergo magnetic hardening, or, after the above-mentioned cooling, this alloy is subjected to hot working at >=500 deg.C so as to orient a crystal axis in a crystalline state in a specific direction and make the magnet magnetically anisotropic or is subjected to hot working at >=500 deg.C and then to heat treatment at >=500 deg.C to undergo magnetic hardening. In this way, the high-efficiency permanent magnet can be manufactured by means of low-temp. and short-time treatment. |
