Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 12 No. 2 April 2002|
Sm2(Co, Fe, Cu, Zr)17 alloys
（State Key Laboratory for Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract:The magnetic properties of Sm2(Co,Fe,Cu,Zr)17 alloys are very sensitive to heat treatments. A magnet with Br of 1.08T, Hci of 2312kA·m-1 and (BH)max of 211.0kJ·m-3 has been obtained after sintering at 1201℃ and aging at 830℃. The magnet has a very low temperature coefficient (β) of -0.18%/℃. The maxim um operating temperature is dramatically higher than commercial magnets. The microstructure analysis shows that Sm2(Co,Fe)17, Sm(Co,Cu)5 and Co2Zr are found in the magnet. The EDAX analysis shows that the cells are enriched in Fe, but depleted in Cu and Zr, whereas the cell boundaries are Cu and Zr enriched, but Fe depleted.
Key words: magnets; temperature coefficient; magnetic and microstructure properties