钨-镍-铁重合金（W heavy alloy, WHA）具有极好的χ、γ的屏蔽性能及耐高温、耐腐蚀特性，被广泛应用于医疗、核技术、航空航天等领域。但其受到高能光子和带电粒子作用会导致辐照损伤引发材料物理性能降级。项目针对辐照微观缺陷与氦扩散至材料表面导致其硬化、氦脆化和肿胀等问题，拟采用金属合金微观结构特色表征手段正电子湮没谱学技术，结合电子显微镜、热脱附谱仪等方法，开展W重合金辐照微观缺陷的形成和热回复机制、缺陷与氦原子相互作用机制、氦泡的热力学行为研究，深入探讨氦泡形核、扩散对合金氦脆及表面组织结构演变的影响，揭示微观缺陷、He泡扩散、纳米丝状结构与材料表面微观结构、性能之间的构效关系。项目成果将积累钨重合金抗辐照和氦脆化性能改进方面的基础数据，为研制安全可靠的高性能钨重合金屏蔽材料提供科学依据和技术支持，具有重要的科学与应用价值。

Tungsten nickel iron heavy alloy (WHA) are widely used in medical, nuclear technology, and aerospace fields because of its excellent χ and γ shielding properties, high temperature and corrosion resistance. Unfortunately, WHA suffers from high-energy photons and charged ions radiation damage induced degradation of material’s physical properties. This project focus research the hardening, helium embrittlement and swelling problem caused by radiation defects and the diffusion of helium to the surface of the material. To understand the process of formation and heat transfer mechanism of irradiation defects; the interaction mechanism between defects and helium atom; and the thermodynamic behavior of helium in WHA, positron annihilation spectroscope is adopted due to its characteristic talent of micro-structure in metal alloys, and combination with TEM, TDS. By analyzing the effects of helium bubble nucleation and diffusion on the evolution of helium embrittlement and surface structure of the alloy, reveal the structure-performance relationships between micro-defects, He bubble diffusion, FUZZ structures with surface micro-structure and properties of materials. The project results will accumulate the data base of WHA anti-irradiation and the improvement of helium embrittlement, and will provide scientific basis and technical support for the development of safe and reliable high-performance WHA shielding materials. It has important scientific and applied value.