在基于兰酸的复合粉中增强磁热效应
Fidel Ivan Reyes Patricio1, Cristhian Antonio Taboada Moreno1, Ana María Bolarín Miró1
1Área Académica de Ciencias de la Tierra y Materiales, Universidad Autónoma del Estado de Hidalgo, Mineral de la Reforma 42184, Mexico.
Materials (Basel, Switzerland)
|November 13, 2025
概括
这项研究开发了一种双相 manganite复合材料,以改善磁性制冷. 陶显示了增强的冷却功率和广泛的操作温度范围,使其适合实际应用.
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
- 热力学是一种热力学.
背景情况:
- 兰矿石具有显著的磁热效应 (MCE),对于磁性制冷至关重要.
- 单个化合物通常具有狭窄的操作温度窗口,限制了实际应用.
- 复合材料提供了一种扩大MCE温度范围的策略.
研究的目的:
- 为了设计和表征一个双相酸陶复合材料.
- 在低磁场下增强磁热效应 (MCE) 和相对冷却功率 (RCP).
- 调查相间合用于扩大操作温度窗口 (OTW) 的潜力.
主要方法:
- 从La0.7Ca0.2Sr0.1MnO3和La0.7Ca0.25Sr0.05MnO3在相同的重量比率中合成一个双相复合物.
- 用于相位分析的X射线衍射 (XRD).
- 温度依赖磁化测量以确定基里温度,并使用阿罗特图分析相位过渡.
主要成果:
- XRD证实了两个正方形金石相的并存,没有二次相.
- 复合材料表现出两个不同的基里温度 (286.8K和307.6K).
- 实现了高相对冷却功率 (RCP) 188.82 J·kg-1和延长的操作温度窗口 (OTW) ~85 K.
结论:
- 与单个相相比,双相复合材料的磁热性能优越,特别是在其广泛的OTW中.
- 接口交换合和应变介导效应是增强MCE和RCP的关键.
- 这种复合材料是一个有希望的候选人,用于在适度磁场下运行的实际磁制冷应用.
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