Patent ID: 9275794
Filing Date: 2016-03-01
CPC Classification: B22F,B32B,C22C,H01F

Claim Text:
1. A method for producing a corrosion-resistant magnet characterized by comprising vapor depositing a film made of Al or an alloy thereof on a surface of an R—Fe—B based sintered magnet at a first average film formation rate set at 0.1 μm/min to 0.4 μm/min until one-third of a desired film thickness is reached and then at a second average film formation rate of 0.2 μm/min to 1 μm/min, the second average film formation rate being always higher than the first average film formation rate, and then forming, on the surface of the deposited film, a chemical conversion film containing at least Zr, V, Al, fluorine, and oxygen as constituent elements and not containing phosphorus, wherein the corrosion-resistant magnet is characterized in that a region of an outer-surface-side half of the thickness of the chemical conversion film has a higher Zr content than a region of a magnet-side half of the thickness of the chemical conversion film.