高熵合金突破了传统以“1-2种元素为主”的合金概念的束缚，从热力学"熵"的角度创新了材料的设计理念，具有优异的力学性能，有望突破传统材料的极限。激光冲击强化是一种新的表面强化技术，可显著提高结构材料在循环载荷作用下的疲劳性能，但激光冲击强化高熵合金的循环变形研究尚未见报道。本项目以非等原子比双相高熵合金Fe50Mn30Co10Cr10为研究对象，系统开展宏观力学实验、微结构表征、本构理论建模等方面的研究，揭示其变形特征及微结构演化规律，阐明高熵合金的微观组织-变形机理-循环响应之间的关联，建立综合考虑位错、孪生和相变等多种塑性变形机制以及激光冲击强化导致的梯度微结构和残余应力对高熵合金循环塑性响应影响的本构模型。本研究将促进固体力学学科材料本构关系研究领域的发展，为高熵合金的强韧化设计和抗疲劳设计提供理论基础，进而促进高熵合金的工程应用。

High entropy alloys (HEAs) break up the shackles of concept that the traditional alloys mainly contain two elements at most. A new philosophy of material design from the point of "entropy" in thermodynamics enables the excellent mechanical performances of HEAs, which are expected to break through the limits of traditional materials. Laser shock peening (LSP) is a new surface strengthening technology. It can change the microstructure of surface material and produce residual compressive stress at a thick enough depth. Therefore, the anti-fatigue performance of materials will be significantly improved by LSP. However, no researches have been done towards the cyclic deformation behavior of high entropy alloy treated with laser shock peening. This project focus on the non-equiatomic high-entropy dual-phase alloys Fe50Mn30Co10Cr10 (at%), and the macroscopic mechanical experiments, microstructural characterizations, and constitutive modeling will be systematically developed. Through this project, we will reveal the cyclic deformation features of HEAs and the evolution laws of microstructures, elaborating the relationships among microstructure, deformation mechanism and cyclic response. Finally, a constitutive model comprehensively considering multiple plastic deformation mechanisms (such as dislocation slipping, twining, phase transformation and so on) will be established, and the effect of gradient microstructures and residual compressive stress resulting from LSP on the cyclic plastic behavior of HEAs will also be considered in this model. This project will benefit the development of the research direction of material constitutive modelling in solid mechanics, and furthermore promote the engineering application of HEAs by providing the theoretical basis for the strength-ductility optimization and anti-fatigue design.