| 摘要 |
PURPOSE:To decrease the contents of Ca and O in Nd-B-Fe powder in particular by adding a specific ratio of a corrosion inhibitor to rinsing water in a process for production consisting in subjecting the resulted product of reaction obtd. by mixing and reduction diffusing of raw material powders to grinding, rinsing, dehydrating, and vacuum drying. CONSTITUTION:The resulted product of reaction obtd. by mixing and reduction diffusing of the raw material powders is ground and is then subjected to rinsing or rinsing diilute acid cleaning rinsing. The water and/or cleaning liquid added with the inhibitor (corrosion inhibitor) at 10<-3>-10<-2>g/l is used for the water tor the rinsing and/or the cleaning liquid for the dilute acid cleaning. An effect of decreasing Ca and O is obtd. by this method. The above-mentioned decreasing effect is substantially nil if the amt. of the inhibitor to be added is below 10<-3>g/l. Said decreasing effect is not improved if the amt. exceeds 10<-2>g/l. Even more, the impurities, such as C, S and N, which are unfavorable for magnetic characteristics increase in such a case. |
