| 摘要 |
PURPOSE:To remarkably improve the corrosion resistance of a magnetic allay by laminatedly coating the surface of an R-TM-B magnetic allay with plural plated layers by specified metals. CONSTITUTION:On the surface of an R-TM-B magnetic base metal alloy having a compsn. constituted of, by weight, 5 to 40% R (the combination of one or >=two kinds among rare earth elements including Y), 50 to 90% TM (denoting transition metals such as Fe, Ni and Co, and in which a part thereof may be substituted by Ga, Al Ti, V, Cr or the other specified metallic or nonmetallic elements) and 0.2 to 8% B, a plated layer of Cu or Ni is formed to 0.1 to 5mum thickness by using an alkaline electroless plating bath of pH>7. On the surface, an electroplated layer of Cu or Ni as an intermediate layer is formed to 1 to 20mum thickness, and on this surface, an electroplated layer of an Ni-P allay as a surface layer is formed to 0.1 to 20mum laminatedly in succession, by which the R-TM-B magnetic alloy excellent in corrosion resistance can be produced. |
