RARE EARTH MAGNET

文件类型：PDF文档
文件大小：410K
A rare earth magnet having excellent corrosion resistance is provided. It has a magnet body (10) containing a rare earth element, and a protective film (20) formed on the magnet body (10). In the protective film (20), a first protective film (21), a second protective film (22) and a third protective film (23) are laminated in this order from the side of the magnet body (10). These are in a polycrystalline state and composed of a metal plated film, for example. The first protective film (21) and the third protective film (23) have a smaller mean crystal grain size than that of the second protective film (22). Microcrystallization of the first protective film (21) can improve the density of the interface between the protective film (20) and the magnet body (10), and decrease the number of pinholes.