PROCESS FOR PRODUCING, THROUGH STRIP CASTING, RAW ALLOY FOR NANOCOMPOSITE TYPE PERMANENT MAGNET

摘要

A process for efficiently producing at low cost a raw alloy for nanocomposite magnets which is mainly amorphous. The process comprises preparing a molten alloy represented by Fe100-x-y-zRxQyMz (wherein R is at least one of praseodymium, neodymium, dysprosium, and terbium; Q is at least one of boron and carbon; M is at least one of cobalt, aluminum, silicon, titanium, vanadium, chromium, manganese, nickel, copper, gallium, zirconium, niobium, molybdenum, silver, platinum, gold, and lead; 1≤x < 6 at.%; 15≤y≤30 at.%; and 0≤z≤7 at.%) and feeding this molten alloy to a cooling roll rotating at a peripheral speed of 3 to 20 m/sec, excluding 20 m/sec, so that the feed rate per unit contact width is in the range of 0.2 to 5.2 kg/min/cm to thereby rapidly cool the alloy by strip casting. Thus, an alloy at least 60 vol.% of which is amorphous can be produced.