磁驱动形状记忆合金结构转变与磁转变耦合及其与功能特性的关联性研究

项目名称： 磁驱动形状记忆合金结构转变与磁转变耦合及其与功能特性的关联性研究

项目编号： No.51471030

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 从道永

作者单位： 北京科技大学

项目金额： 85万元

中文摘要： 磁驱动形状记忆合金能够产生基于结构转变与磁性转变耦合的多功能特性（磁致形状记忆效应、巨磁热效应、巨磁阻效应等）。作为重要的科学问题，磁驱动形状记忆合金结构转变与磁性转变的耦合机理以及耦合特征参数（耦合温度、耦合温区跨度、耦合强弱程度、耦合热效应等）与功能特性的内在关联性亟待澄清。本项目拟以NiMn基磁驱动形状记忆合金为研究对象，探索结构转变与磁性转变的热力学与动力学新机制，阐明不同结构和磁性状态的起源与形成机理；揭示结构转变与磁性转变的耦合机理，澄清微观磁性与结构基元的相互作用机制（包括应变玻璃与自旋玻璃的多玻璃态耦合规律、纳米应变畴和磁性团簇的交互作用机制）；揭示耦合特征参数与功能特性的内在关联性，建立基于耦合特征参数调控优化多功能特性的有效统一物理模型。本研究对丰富和发展磁驱动马氏体相变理论、研发新型高性能磁驱动形状记忆材料具有重要的理论意义和实际价值。

中文关键词： 形状记忆合金；马氏体相变；功能特性

英文摘要： Magnetic shape memory alloys (MSMAs) exhibit multifunctional properties (magnetic shape memory effect, giant magnetocaloric effect, giant magnetoresistance, etc.) based on the coupling between structural and magnetic transitions. As important scientific issues, the coupling mechanism of structural and magnetic transitions of MSMAs and the intrinsic correlation between the characteristic coupling parameters (coupling temperature, coupling temperature interval, coupling intensity, coupling entropy change, etc.) and the functional properties remain unclear and the clarification of these scientific issues is urgently needed. With NiMn-based MSMAs as the research object, the present project aims to explore the new thermodynamic and dynamic mechanisms responsible for structural and magnetic transitions and elucidate the origin and formation mechanisms for different structural and magnetic states, to reveal the coupling mechanism for structural and magnetic transitions and clarify the interaction laws for the microscopic magnetic and structural units (including the coupling laws for the multi-glassy state of strain glass and spin glass, and the interplay mechanisms for the nano-sized strain domains and magnetic clusters), and to disclose the intrinsic correlation between the characteristic coupling parameters and the functional properties and establish the effective and integrated physical model for optimizing functional properties based on tuning the characteristic coupling parameters. This study is of both great theoretical significance and practical interest for enriching and developing the theory on magnetically driven martensitic transformation and for designing novel high-performance magnetic shape memory materials.

英文关键词： Shape memory alloys;Martensitic transformation;Functional properties