宝贵元素对MnPt合金结构,磁性和弹性的影响:一项第一原则研究
Ramogohlo Diale1, Phuti Ngoepe2, Hasani Chauke2
1Advanced Materials Division, Mintek, Private Bag X 3015, Randburg 2125, South Africa.
Materials (Basel, Switzerland)
|April 9, 2024
概括
本研究探讨在- (MnPt) 合金中用 (Pd),金 (Au) 和银 (Ag) 替代 (Pt) 进行数据存储. 添加保持了铁磁性和稳定性,这表明了螺旋电子应用的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 计算材料科学科学 计算材料科学
背景情况:
- - (MnPt) 合金表现出高稳定性和尼尔温度,使它们成为数据存储的有希望的材料.
- 实验研究表明,MnPt合金具有室温铁磁性 (FM) 特性.
- 研究MnPt中的替代对于优化自旋电子应用的磁性质至关重要.
研究的目的:
- 研究Pt与Pd,Au和Ag的部分替代对MnPt合金的磁性和机械性能的影响.
- 用密度函数理论评估Mn50Pt50-xMx (M = Pd, Au, Ag) 合金的热力学稳定性和可成型性.
- 为了确定未来磁铁的潜在新组成,用于旋转子应用.
主要方法:
- 密度函数理论 (DFT) 的计算被用来研究Mn50Pt50-xMx (M = Pd, Au, Ag, x = 6.25, 12.5, 18.75) 的合金.
- 热力学稳定性通过形成热计算来评估.
- 计算了机械性能,包括弹性和波松比,以评估稳定性和柔性.
- 对不同成分的磁性,特别是铁磁性进行了分析.
主要成果:
- B2 Mn50Pt50-xPdx合金表现出热力学稳定性,形成热量的负值与原始MnPt相当.
- 弹性计算表明B2 Mn50Pt50-xPdx合金在研究的组成范围内容易发生马氏体变化.
- 增加的Pd,Ag和Au度提高了B2 Mn50Pt50-xMx化合物的可塑性.
- 铁磁性与Pd替代性保持,但与Au和Ag显著减少.
结论:
- DFT计算成功地预测了MnPt合金的稳定性和性能.
- B2 Mn50Pt50-xPdx合金具有热力学稳定性和延展性,保持铁磁性,使其适合于自旋电子应用.
- 部分替代提供了一个可行的途径来调整基于MnPt的磁性材料的性能,用于先进的数据存储.
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