Gd基非晶微丝磁热效应及其调控机制

Gd-based amorphous microwires with one-dimensional structure and excellent magnetocaloric effect (MCE) and exhibit significant advantages in the applications of magnetic refrigeration. The research will focus on exploring the MCE performance tailoring mechanism based on the melt-extracted amorphous microwires. The microstructure change corresponding with MCE improvement will be explained by thermal refining inducing the improvements of circumferential magnetic domain, innerstress and cluster structures; The impacts of magnetic coupling on MCE will be confirmed by the MCE comparison between single and multi-wires, and characterized by variation of wire number, distance and exterior stress; The MCE anisotropy resulting from the wire-shape will be exhibited, and it is difference between single-wire and multi-wires when at applied field with different directions, the relationship with magnetic coupling will also be discussed; The refrigerating efficiency will be enhanced by multicomponent composite, thus establish the theoretical model between MCE of composite and its components and obtain “Table-like” MCE functional materials. The above research will show the MCE nature of Gd-based amorphous wires and promote their applications in magnetic refrigeration.

Gd基非晶微丝因其准一维的几何结构和优异的磁热性能在磁制冷领域具有明显的技术优势。本项目拟以熔体抽拉GdAlCo非晶磁热微丝为研究对象，以揭示微丝磁热效应主要影响因素及性能调控机制等为研究目标：通过电流调制处理改善微丝环向磁畴和微观团簇原子排布、释放残余应力，建立微丝微结构与磁热性能的联系；基于单根微丝与集束微丝磁热效应的对比分析，阐明微丝间磁交互作用，获取微丝数量、间距及外应力等因素变化与磁热性能的对应关系，以及影响微丝间磁交互作用的因素；研究单根微丝及集束微丝之间磁热各向异性差异与不同方向上微丝间耦合作用的相关性；最后采用多成分微丝复合的方式拓宽工作温区，建立复合微丝结构磁热性能与各成分磁热性能关系的量化模型，设计类“平台状”微丝功能复合材料。上述研究可为微丝磁制冷工质结构设计及其系统应用提供理论支撑。

Gd基非晶微丝因其准一维的几何结构和优异的磁热性能在磁制冷领域具有明显的技术优势。本项目拟以熔体抽拉GdAlCo非晶磁热微丝为研究对象，以揭示微丝磁热效应主要影响因素及性能调控机制等为研究目标：通过电流调制处理改善微丝环向磁畴和微观团簇原子排布、释放残余应力，建立微丝微结构与磁热性能的联系；基于单根微丝与集束微丝磁热效应的对比分析，阐明微丝间磁交互作用，获取微丝数量、间距及外应力等因素变化与磁热性能的对应关系，以及影响微丝间磁交互作用的因素；研究单根微丝及集束微丝之间磁热各向异性差异与不同方向上微丝间耦合作用的相关性；最后采用多成分微丝复合的方式拓宽工作温区，建立复合微丝结构磁热性能与各成分磁热性能关系的量化模型，设计类“平台状”微丝功能复合材料。上述研究可为微丝磁制冷工质结构设计及其系统应用提供理论支撑。