METHOD FOR PREPARING HIGH-COERCIVITY SINTEREDND-FE-B AND PRODUCT OBTAINED THEREBY

文件类型：PDF文档
文件大小：703K
Disclosed is a method for preparing a high-coercivity sintered Nd-Fe-B, comprising : preparing a main phase alloy powder and a grain boundary phase alloy powder; uniformly mixing the prepared grain boundary phase alloy powder and main phase alloy powder in a protective medium protected by nitrogen gas or argon gas, the grain boundary phase alloy powder added being 0.1-10% by weight; orientation-compressing and cold-isostatic-pressing the mixed alloy powder; in a vacuum sintering furnace, sintering a compressed magnet block at 1000-1100˚C for 2-4 hours, and performing a primary tempering at 800-950˚C for 2-4 hours and a secondary tempering at 450-650˚C for 2-4 hours to obtain the sintered Nd-Fe-B. Also disclosed is a high-coercivity sintered Nd-Fe-B. The present invention reduces a wetting temperature between the grain boundary phase and the main phase via a low melting point auxiliary alloy, and extends wetting time, thus improving the utilization of heavy rare earths, and reducing the usage amount of the rare earths; and the preparation method has a simple process and low cost, thus facilitating large-scale production.