Patent ID: 9281107
Filing Date: 2016-03-08
CPC Classification: B22F,C22C,H01F

Claim Text:
1. A manufacturing method of a rare-earth permanent magnet comprising steps of: milling magnet material into magnet powder: preparing a mixture by mixing the magnet powder and any one of three kinds of binders obtaining a green sheet by forming the mixture into a sheet-like shape, the mixture is formed by employing a hot melt coating in which the mixture is heated to melt, and turns into a fluid state and then is spread; removing the binder by holding the green sheet for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so that a residual carbon content contained in the permanent magnet after sintering is 1500 ppm or less and a residual oxygen content contained in the permanent magnet after sintering is 2000 ppm or less; and sintering the green sheet from which the binder has been removed by raising temperature up to sintering temperature.