Author(s): |
Chuan Chen, School of Materials and Engineering, South China University of Technology, Guangzhou 510640, China Zhong-wu Liu, School of Materials and Engineering, South China University of Technology, Guangzhou 510640, China Xi-chun Zhong, School of Materials and Engineering, South China University of Technology, Guangzhou 510640, China Hong-ya Yu, School of Materials and Engineering, South China University of Technology, Guangzhou 510640, China Wan-qi Qiu, School of Materials and Engineering, South China University of Technology, Guangzhou 510640, China De-chang Zeng, School of Materials and Engineering, South China University of Technology, Guangzhou 510640, China Raju V.ramanujan, School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore |
Abstract: |
The Mn-Al alloy ribbons with hexagon ε single-phase have been prepared by melt spinning. The transformations of ε → τ at about 500℃ and τ → ε at about 800℃ are obtained using the analysis of DSC, X-ray diffraction and MnAl phase diagram. The effects of the composition and annealing process on the phase structure and magnetic properties have been investigated. It was found that moderate carbon addition can promote the formation of τ-phase and obtain improved magnetic properties. Mn53.3Al45C1.7 sample annealed at 650 ℃ for 10 minutes has the best magnetic properties of JS = 0.83 T, Br = 0.30 T, HC = 123 kA, and (BH)max = 12.24 kJ/m3. Doping rare earth elements Dy and Pr can slightly improve the magnetic properties, especially JS and Br. It was also found that C cannot be replaced by B and MnAlB cannot form stable hard magnetic phase, and the instable ε-phase may decompose into intermediate phases during annealing.
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