BONDED MAGNET AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To manufacture a bonded magnet which is improved in corrosion resistance and mechanical strength. SOLUTION: A main body 12 of a rare-earth bonded magnet 10 is obtained by injection or compression-molding a kneaded material of rare-earth magnet powder and a binder composed of a high polymer material into a required shape. It is preferable to adjust the mixing ratio of the rare-earth magnet powder and an epoxy resin which is used as the high polymer material as the high polymer material in the main body 12 to 90-99 wt.% and 1-10 wt.%, respectively. The entire surface of the main body 12 is covered with a first resin film 14 composed of an epoxy resin, which is a high polymer material and having a thickness of 5-50 μm. Then the entire surface of the first resin film 14 is furthermore covered with a second resin film 16 which is composed of an epoxy resin and having a thickness of 1-20 μm.