R a-T a-B permanent magnet material and its preparation

文件类型：PDF文档
文件大小：244K
The present invention relates to an R-T-B permanent magnet material, said R-T-B permanent magnet material being RxTyTmqBz, where 13 ≤ x ≤ 15.5, 0.5 ≤ q ≤3, 0.85 ≤ z ≤1, and y = 100 - x - q - z; R is LRaHR1-a, where LR is one of or a combination of two of Pr, Nd, and PrNd, and HR is one of or the combination of two of Dy and Tb, where 0.95 ≤ a ≤ 1; T is one of or the combination of Fe and Co; Tm is a transition metal. Also disclosed is a method for manufacturing the R-T-B permanent magnet material. The advantage is that the use of a magnetron sputtering apparatus to coat a heavy rare earth film on an alloy sheet does not require a long period of heat dissipating treatment, thus obtaining a "core-shell" structure and substantially increasing the coercivity of the magnet. Compared to traditional techniques, given the identical content of heavy rare earth, the present invention provides for higher coercivity and maximum energy product.