基于铁磁晶格畴序构调控的高灵敏窄滞后磁致伸缩材料研究

Magnetostrictive materials have the intelligent characteristics of sensing magnetic fields and generating driving, and are widely used in high-tech and advanced industries. In recent years, the rapid development and competition in the high-tech field has placed great demands on the high performance (high sensitivity and low hysteresis) of magnetostrictive materials, but it is difficult to achieve breakthroughs in performance based on traditional theoretical research methods. Our previous research shows that the application of the "ferromagnetic strain glass" and "ferromagnetic morphotropic phase boundary" principles to the design of magnetostrictive materials is expected to provide new ideas. On the basis of the previous work, the project intends to take the ferromagnetic lattice domain as the functional element, and the "long-range disorder & short-range order" (corresponding to ferromagnetic strain glass) and "two-phase-coexistence around the phase boundary derived from the triple-point" (corresponding to ferromagnetic morphotropic phase boundary) as ordering structure, to study the interaction mechanism between the functional element and the ordering structure. A physical model based on the "functional element + ordering structure" is established and will be applied to the new magnetic functional materials. We aim to reveal the mechanism for the high-sensitivity and low-hysteresis magnetostrictive effect induced by the ferromagnetic strained glass and ferromagnetic morphotropic phase boundary, break through the technical bottleneck of magnetostrictive material design and preparation, and lay the technical foundation for the development and application of high performance magnetostrictive materials.

磁致伸缩材料具有感知磁场并产生驱动的智能特性，广泛应用于高技术和先进工业领域。近年来高科技领域的快速发展及竞争对磁致伸缩材料的高性能化(高灵敏、窄滞后)提出了迫切需求，但是基于传统理论的研究方法难以实现性能和技术的突破。我们前期的研究表明，将“应变玻璃”和“准同型相界”原理应用于磁致伸缩材料的设计及制备，有望为高性能磁致伸缩材料的研发提供新思路。本项目拟在前期工作的基础上，以铁磁晶格畴为功能基元，以铁磁应变玻璃和铁磁准同型相界分别对应的“长程无序&短程有序”和“由三相点衍生的铁磁相界区域的两相共存态”为序构，研究功能基元与序构的相互作用机制，建立基于“功能基元+序构”调控的物理模型并应用于新型磁致伸缩材料研究，揭示铁磁应变玻璃和铁磁准同型相界诱发高灵敏、窄滞后磁致伸缩效应的物理机制，突破磁致伸缩材料设计和制备的技术瓶颈，为高性能磁致伸缩材料的研发及应用奠定技术基础。

磁致伸缩材料具有感知磁场并产生驱动的智能特性，广泛应用于高技术和先进工业领域。近年来高科技领域的快速发展及竞争对磁致伸缩材料的高性能化(高灵敏、窄滞后)提出了迫切需求，但是基于传统理论的研究方法难以实现性能和技术的突破。本项目在前期研究工作的基础上，以铁磁晶格畴为功能基元，以铁磁准同型相界、或铁磁应变玻璃、或调幅分解结构序构，研究功能基元与序构的相互作用机制，建立基于“功能基元+序构”调控的物理模型并应用于新型磁致伸缩材料研究。本项目聚焦在如下3个方向开展了深入的研究和探索：（1）铁磁晶格畴（功能基元）形成序构的物理机制；（2）利用功能基元序构调控思路设计和制备多种高性能磁致伸缩材料材料；（3）探索基于新原理产生的相关物理效应。本项目严格按照项目计划开展课题研究，基于功能序构调控思路，分别在Laves相合金与Fe基合金两类材料体系中制备出大磁致伸缩材料Tb0.5Dy0.5(Fe0.5Co0.5)2、Tb0.5Dy0.5Co1.95和FeGa-Pt，以及兼具大磁导率和近零磁致伸缩的Fe20Co80合金，完成了既定研究目标。此外，受功能基元序构调控思路的启发，在本项目资助下，团队在低铅大压电材料、零场交换偏置合金、超顺磁纳米颗粒、场致自旋重取向材料等也进行了大胆的探索，取得了一些有意义的研究成果。研究成果发表在Advanced Functional Materials, Nano Energy, APL Materials, Acta Materialia, Scripta Materialia, Physical Review B等国际著名期刊（SCI论文38篇），获得授权专利3项，参加国内学术会议并做特邀报告3次。