Permanent magnet alloy having improved resistance

摘要

A permanent magnet made of an R-Fe-B-C or R-Fe-Co-B-C based alloy, where R is at least one rare-earth element, comprising individual magnetic crystal grains that are covered with an oxidation-resistant protective film. The protective film surrounding the individual magnetic crystal grains having a thickness of 0.001-30 mu m and 0.05-16 wt. % of the protective film comprising C.