| 摘要 |
An Fe-B-R based permanent magnet has a metal oxide film having a thickness of 0.01 mu m to 1 mu m on its surface with a metal film interposed therebetween. Thus, the film is excellent in adhesion to the surface of the magnet. Even if the permanent magnet is left to stand under high-temperature and high-humidity of a temperature of 80 DEG C and a relative humidity of 90 % for a long period of time, the magnetic characteristic of the magnet cannot be degraded. The magnet has a thermal shock resistance enough to resist even a heat cycle for a long period of time in a temperature range of -40 DEG C to 85 DEG C, and can exhibit a stable high magnetic characteristic. Therefore, it is possible to produce an Fe-B-R based permanent magnet having a corrosion-resistant film free from hexa-valent chromium. |
