Rare earth/iron/boron-based permanent magnet alloy composition

摘要

Disclosed is a rare earth/iron/boron-based permanent magnet alloy composition capable of giving, by a powder metallurgical process, a permanent magnet having excellent coercive force and residual magnetization as well as good squareness ratio of the hysteresis loop. The magnet alloy composition consists of:(a) from 28 to 35% by weight of a rare earth element selected from the group consisting of neodymium, praseodymium, dysprosium, terbium and holmium;(b) from 0.1 to 3.6% by weight of cobalt;(c) from 0.9 to 1.3% by weight of boron;(d) from 0.05 to 1.0% by weight of aluminum;(e) from 0.02 to 0.25% by weight of copper;(f) from 0.02 to 0.3% by weight of zirconium or chromium;(g) from 0.03 to 0.1% by weight of carbon;(h) from 0.1 to 0.8% by weight of oxygen;(i) from 0.002 to 0.2% by weight of nitrogen; and(j) the balance to 100% by weight of iron and unavoidable impurity elements.