Mechanical alloying and theoretical studies of MnAl(C) magnets

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:462

Article

Van Tang Nguyen^1,2  Calvayrac, Florent¹  Bajorek, Anna^3,4  Randrianantoandro, Nirina¹ 

[1] Le Mans Univ, Inst Mol & Mat Mans, UMR CNRS 6283, Ave Olivier Messiaen, F-72085 Le Mans 9, France

[2] Univ Sci & Technol Hanoi, Vietnam Acad Sci & Technol, Dept Adv Mat Sci & Nanotechnol, 18 Hoang Quoc Viet, Hanoi, Vietnam

[3] Univ Silesia Katowice, A Chelkowski Inst Phys, Uniwersytecka 4, PL-40007 Katowice, Poland

[4] Univ Silesia Katowice, Silesian Ctr Educ & Interdisciplinary Res, 75 Pulku Piechoty 1A, PL-41500 Chorzow, Poland

关键词: MnAl(C) alloys;    Ferromagnetic phase;    Mechanical alloying;    Ab initio calculation;   

DOI  :  10.1016/j.jmmm.2018.05.001

来源: Elsevier

【 摘 要 】

Mn55Al45, Mn55Al44C1, Mn52.2Al45.8C2 and Mn54.2Al43.8C2 were synthesized by the mechanical alloying method. It was the first time that a high purity tau phase up to 99% of weight percentage was obtained in Mn54.2Al43.8C2, which gave the highest saturation magnetization M-s = 570 kAm (1) ever reported by mechanical alloying up to date. The crystallite size of the tau phase of MnAl(C) alloy decreased with increasing carbon doping, varying from 79 to 159 nm. Additionally, the coercivity (H-c) was found to be inversely proportional to the crystallite size of tau phase. Effect of doping carbon and its position in the tau phase of MnAl(C) alloy were also investigated for the first time by first-principle calculations. It was found that by inserting carbon at the interstitial site in the tetragonal structure, a strong stabilization effect and an expansion of unit cell were observed, which are in good agreement with the experimental results. Moreover, our results indicate that carbon doping reduces the magnetic moment of Mn. (C) 2018 Elsevier B.V. All rights reserved.

【 授权许可】

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