The rare-earth permanent magnet

文件类型：PDF文档
文件大小：74K
PROBLEM TO BE SOLVED : To provide a manufacturing method for a high-density R-Fe-B nano composite bulk magnet in excellent magnet property and high electric resistance. SOLUTION : An initial material comprises a powder whose each particle is amorphous by at least 30 vol% which constitutes a quench alloy powder for manufacturing an R-Fe-B nano composite magnet comprising hard magnetic phase and soft magnetic phase, and the insulating component whose volume resistivity is 1×10-1Ωcm or higher. In a first manufacturing method, the initial material is hot molded under a pressure of at least 10 MPa at the temperature of crystallization of quench alloy powder to 850°C. In a second manufacturing method, the initial material is hot molded under a pressure of at least 10 MPa at 400°C to the temperature of crystallization of quench alloy powder. Thus, a high-density bulk is obtained which is thermally crystallized at the temperature of crystallization of quench alloy powder to 850°C to obtain a high-density bulk magnet whose density is 6.5 g/cm3or higher. COPYRIGHT : (C)2003, JPO