Ti3AlC2属于典型的MAX相材料，是一类高性能综合性陶瓷材料，兼具金属和陶瓷性能，被认为是非常有潜力的未来先进核能装置的新型候选材料。但是，在材料中较低的He含量与损伤剂量比（约几—几十appmHe/dpa）的情况下He相关缺陷的形成和演化行为仍不清楚，本项目依托中科院近代物理所（IMP, CAS） 320 kV 高电荷态离子综合研究平台开展Ti3AlC2的C、He单束及混合束辐照实验；在材料中形成较低的appmHe/dpa比值，模拟反应堆环境下中子辐照情况—大量移位损伤产生同时嬗变He的掺杂；通过与单束辐照实验结果对比，研究C/He混合束轰击引起Ti3AlC2材料中缺陷（如He-空位复合体或He泡）的形成特征及演化行为。希望通过本项目的开展更深入的认识和理解MAX相材料中的一些He相关行为，以此为将来建造新一代先进核反应堆的选材方面提供一些科学依据和参考。

Ti3AlC2 is a representative material of MAX phase family which belongs among high-performance ceramic materials. This material, which combines benefits of metal and ceramics, is considered to be a very promising new candidate material for future advanced nuclear device. But there are still some scientific issues need to be clarified, one of which is the formation of He related defects and their evolution under lower level ratios of He concentration to damage dose (about several — dozens appmHe/dpa). This project is based on the experimental conditions of multiple particle irradiation (single-beam C, He and their mixed ion beam) provided by 320 kV integrated research platform of highly charged ions in IMP, CAS. C/He mixed ion beam could create the lower level ratios of appmHe/dpa in Ti3AlC2, simulating neutron irradiation situation in reactor environment -- a large of displacement damage producing simultaneously transmutation He doping. Comparing with the experimental results of single-beam (He or C) irradiation, we will carry out the study on formation and evolution of defects (such as He-vacancy complexes or He bubbles) in Ti3AlC2 under mixed ion beam irradiation. We hope this project could promote in-depth understanding of the He-related behavior in MAX phase materials, and provide scientific basis and data for the selection of materials in our future advanced nuclear device.