Effect of Sm Volatilization on Magnetic Microstructures of Sintered Sm(Co,Fe,Cu,Zr)z Magnets at High Temperatures
XIA Ai-Lin1, FANG Yi-Kun1, GUO Zhao-Hui2, LI Wei2, HAN Bao-Shan1
1State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080
2Division of Functional Materials, Central Iron and Steel Research Institute, Beijing 100081
Effect of Sm Volatilization on Magnetic Microstructures of Sintered Sm(Co,Fe,Cu,Zr)z Magnets at High Temperatures
1State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080
2Division of Functional Materials, Central Iron and Steel Research Institute, Beijing 100081
Abstract：We present a magnetic force microscopy study of surface magnetic microstructure changes at high temperatures in 2:17-type Sm(Co,Fe,Cu,Zr)z (z～7.4) magnets. Surface magnetic microstructures are found to change greatly in parallel and vertical specimens after heat-treatment at 400°C for one hour in vacuum of 10-5Torr with Ar gas as protecting atmosphere. Changes of microstructures are attributed to the formation of a soft-magnetic surfaces layer in the specimens, resulting from Sm volatilization due to high temperature. This hypothesis is further confirmed by the heat-treatment experiments at 400°C for 0.5h and 2h. Finally, the existence of the soft-magnetic layers, which consist primarily of Fe--Co compounds, is verified by the results of both XRD and XPS of the vertical specimens before and after heat-treatment.
XIA Ai-Lin;FANG Yi-Kun;GUO Zhao-Hui;LI Wei;HAN Bao-Shan. Effect of Sm Volatilization on Magnetic Microstructures of Sintered Sm(Co,Fe,Cu,Zr)z Magnets at High Temperatures[J]. 中国物理快报, 2006, 23(5): 1289-1292.
XIA Ai-Lin, FANG Yi-Kun, GUO Zhao-Hui, LI Wei, HAN Bao-Shan. Effect of Sm Volatilization on Magnetic Microstructures of Sintered Sm(Co,Fe,Cu,Zr)z Magnets at High Temperatures. Chin. Phys. Lett., 2006, 23(5): 1289-1292.
2006, Vol. 23 
