1. Effect of Isothermal Aging Time on Magnetic Properties and Microstructure of Sm1–xDyx(Co0.695Fe0.2Cu0.08Zr0.025)7.2 Magnets.
- Author
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Li, Tianyi, Liu, Zhuang, Zhang, Chaoyue, Xue, Zhiqin, Liu, Lei, Chen, Renjie, Feng, Zaixin, Lee, Don, and Yan, Aru
- Subjects
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SAMARIUM compounds , *ISOTHERMAL processes , *METAL microstructure , *MAGNETIC properties of metals , *CRYSTAL structure - Abstract
The ordering process of 2:17R disordered phase with microtwin structure is a very important process during aging in 2:17-type Sm–Co magnets. In this paper, Sm1–xDyx(Co0.695Fe0.2Cu0.08Zr0.025)7.2 x = 0, 0.5) magnets with different degrees of ordering were prepared. The effect of different isothermal aging times on the magnetic properties of magnets with microtwin structure has been investigated. After isothermal aging for 0, 0.5, 2, 6, and 12 h, the coercivity and remanence of magnets without Dy doped increased gradually, while almost no change in the coercivity and remanence is observed in magnets with x = 0.5. After the slow cooling process, the coercivity about 20 kOe is obtained in all Dy-free magnets with different aging times. On the contrary, with an increase in the ordering degree of 2:17R disordered phase, the coercivity of Dy-doped magnets at room temperature enhances from 5.82 to 7.88 kOe. The temperature coefficient of abnormal coercivity between 20 °C and 100 °C of Sm0.5Dy0.5(Co0.695Fe0.2Cu0.08Zr0.025)7.2 magnets with isothermal aging for 12, 20, and 40 h reduces from +0.176%/°C to +0.065%/°C, which could be due to more content of Dy diffuse from cell boundary to cell phase. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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