氦粒子辐照Ti-Ni记忆合金相界面结构与弹热效应关联性研究

基于应力诱发马氏体相变使记忆合金升温和降温的弹热制冷技术已成为最有希望发展的固态制冷技术。本课题提出采用He粒子辐照引入晶体缺陷，调控相界面运动特征，影响应力对温度敏感性，提高记忆合金微丝弹热效应的新思路。拟从辐照诱发多类型缺陷的形成及演变入手，探明辐照缺陷与母相/马氏体相界面原子交互作用，阐明缺陷作用下相界面结构演变及其运动规律，系统研究相界面运动特征对应力诱发马氏体相变和应力敏感性的影响因素与规律，结合辐照缺陷对弹热过程中绝热温变和等温熵变的影响规律，建立辐照缺陷—相界面结构及其可动性—弹热效应之间的内在关联性，揭示辐照提高记忆合金弹热效应的物理本质，为新型高效弹热制冷材料开发提供新思路和新途径。

Elastocaloric refrigeration technology based on stress-induced martensitic transformation to heat up and cool down the shape memory alloy has become the most promising one in solid-state refrigeration filed. In present project, He particle irradiation was proposed as a new method to introduce defects and tailor phase interface mobility characteristics, effect stress sensitivity and improve elastocaloric effect of shape memory alloy microwires. We planned to start with the formation and evolution of multiple type irradiation defects, to explore the interaction between irradiation defects and interface of martensite and austenite and to clarify the microstructure evolution and mobility law of phase interface under irradiation and the effect on the stress-induced martensitic transformation and stress sensitivity. Combining the influence of defects on the adiabatic temperature change and isothermal entropy change during elastocaloric process, we establish the internal correlation between irradiation defect，phase interface mobility and elastocaloric effect, and reveal the mechanism of improvement on elastocaloric effect. This proposal will provide a new idea and method for developing high efficiency elastocaloric refrigeration materials.