| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a hard magnetic composition which contains a ThMn<SB>12</SB>type crystal phase and has high magnetic properties. <P>SOLUTION: The manufacturing method comprises preparing an alloy material containing the ThMn<SB>12</SB>type crystal phase, and heating and keeping the alloy material under a pressurized atmosphere containing N to nitride it. The alloy material preferably has a chemical composition which is expressed by the general formula: R1<SB>1-x</SB>R2<SB>x</SB>(Ti<SB>y</SB>Fe<SB>100-y-w</SB>Co<SB>w</SB>)<SB>z</SB>Si<SB>u</SB>, (wherein R1 is one or two elements of rare earth elements including Y, while Nd occupies 50% or more of R1; and R2 is one or two elements of Zr and Hf), and has such molar ratios of the general formula as to make x into 0.18 or less, y into 5 to 12.3, z into 11 to 12.8, u into 0.1 to 2.3, w into 0 to 30, and (the total of each molar ratio of Fe + Co +Ti + Si) / (the total of each molar ratio of R1 + R2) larger than 12. The pressure in the pressurized atmosphere is preferably controlled to 0.15 to 5.0 MPa. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
