| 摘要 |
PURPOSE:The permanent magnet of high performance obtainable by heat treating Sm-Co-Cu-Fe-Zr base magnet alloy thereby making the large portion of its structure to the single phase of the intermetallic compound of the specific composition. CONSTITUTION:This material has the composition expressed by the following formula wherein the content ratio of Sm and transition metal is around 2:17 and forms a single phase. Sm2(CoCuFeZr)17 and 22.0<=Sm<24.0, 5.0<=Cu<=10.0, 12.8<=Fe<=18.0, 0.5<=Zr<=2.5 and the rest is constituted by Co. PREPARATION:The magnet alloy of the abovementioned composition is melted in a high frequency furnace and is cast to ingot. The ingot is homogenized for 48 hours at 1200 deg.C in a vacuum vessel. Next, it is heat treated for 2 hours at 1500 deg.C, after which it is quenched in Ar flow. Further, it is heat treated for 30 minutes to 5 hours at 700 to 900 deg.C then for 8 hours at 400 to 500 deg.C. The permanent magnet of high performance in which more than 90% of the structure consists of the single phase of Sm2(CoCuFeZr)17 is obtained. |
