Heusler型磁相变合金先进原位表征与功能设计

Heusler-type magnetic phase-transition alloys: Advanced in-situ characterization and high-performance design

Heusler型磁相变合金是一类新型智能材料,能够在外加磁场下发生相变,从而产生磁致形状记忆效应、磁超弹性、磁热效应、磁阻效应等多功能特性,作为传感、驱动和固态制冷材料在航空航天、国防、能源等领域具有广阔的应用前景.此类合金的晶体结构、磁结构和多场耦合下的相变对其功能特性具有重要影响.中子散射技术为Heusler型磁相变合金的晶体结构、磁结构和晶格动力学研究提供了独特的条件,原位中子散射和同步辐射高能X射线衍射技术为多场耦合下的磁-结构相变研究提供了理想的工具.本文综述了基于先进中子散射技术和同步辐射技术对Heusler型磁相变合金晶体结构、磁结构和外场耦合下相变的原位研究,以及基于这些先进原位表征的合金高性能设计,以期能为将来高性能磁相变材料的设计和研制提供借鉴.

Heusler-type magnetic phase-transition alloys are a new kind of intelligent materials. They exhibit a magnetic-fieldinduced phase transition and thus show fascinating multifunctional properties including magnetic shape memory effect,magnetic superelasticity, magnetocaloric effect, and magnetoresistance. As a result, these alloys show promising prospects of applications as sensors, actuators and solid-state refrigerants in the fields of aeronautics and astronautics,defense, energy, etc. The crystal structure, magnetic structure and magnetostructural transition under the coupling of multiple external fields are of great importance for the multifunctional properties of these alloys. Neutron scattering provides a unique technique for studying the crystal structure, magnetic structure and lattice dynamics in these alloys,and in-situ neutron scattering and synchrotron high-energy X-ray diffraction techniques offer a powerful tool to study the magnetostructural transition under the coupling of multiple external fields. The present paper reviews the recent progress on the in-situ study of crystal structure, magnetic structure and phase transition under the coupling of multiple external fields in the Heusler-type magnetic phase-transition alloys using the advanced neutron scattering and synchrotron radiation techniques, as well as the high-performance design based on the in-situ characterization, with an aim to provide some guidance for the future design and development of high-performance magnetic phase-transition materials.