High-performance radiation tolerance materials are crucial for the success of future advanced nuclear reactors. In this paper, we present a further investigation that the “vein-like” nanochannel films can enhance radiation tolerance under ion irradiation at high temperature and post-irradiation annealing. The chromium nitride (CrN) nanochannel films with different nanochannel densities and the compact CrN film are chosen as a model system for these studies. Microstructural evolution of these films were investigated using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Elastic Recoil Detection (ERD) and Grazing Incidence X-ray Diffraction (GIXRD). Under the high fluence He⁺ ion irradiation at 500 °C, small He bubbles with low bubble densities are observed in the irradiated nanochannel CrN films, while the aligned large He bubbles, blistering and texture reconstruction are found in the irradiated compact CrN film. For the heavy Ar²⁺ ion irradiation at 500 °C, the microstructure of the nanochannel CrN RT film is more stable than that of the compact CrN film due to the effective releasing of defects via the nanochannel structure. Under the He⁺ ion irradiation and subsequent annealing, compared with the compact film, the nanochannel films have excellent performance for the suppression of He bubble growth and possess the strong microstructural stability. Basing on the analysis on the sizes and number densities of bubbles as well as the concentrations of He retained in the nanochannel CrN films and the compact CrN film under different experimental conditions, potential mechanism for the enhanced radiation tolerance are discussed. Nanochannels play a crucial role on the release of He/defects under ion irradiation. We conclude that the tailored “vein-like” nanochannel structure may be used as advanced radiation tolerance materials for future nuclear reactors.

高性能耐辐射材料对于未来先进核反应堆的成功至关重要。在本文中，我们提出了进一步的研究，即“类静脉”纳米通道膜可以增强高温下离子辐照和辐照后退火下的辐射耐受性。选择具有不同纳米通道密度的氮化铬（CrN）纳米通道膜和致密的CrN膜作为这些研究的模型系统。使用透射电子显微镜（TEM），扫描电子显微镜（SEM），弹性反冲检测（ERD）和掠入射X射线衍射（GIXRD）研究了这些薄膜的微观结构演变。在高通量下，他⁺在500°C的离子辐照下，在被辐照的纳米通道CrN薄膜中观察到低气泡密度的小He气泡，而在被辐照的CrN致密膜中发现取向的大He气泡，起泡和织构重构。对于500°C的重Ar ²⁺离子辐照，由于通过纳米通道结构有效释放了缺陷，因此纳米通道CrN RT薄膜的微观结构比紧凑型CrN薄膜更稳定。在他⁺离子辐照和随后的退火，与致密膜相比，纳米通道膜在抑制He气泡生长方面具有出色的性能，并具有很强的微观结构稳定性。在分析不同实验条件下，纳米通道CrN薄膜和致密CrN薄膜中气泡的大小，数量密度以及氦的浓度分析的基础上，探讨了提高耐辐射性的潜在机理。纳米通道对离子辐照下He /缺陷的释放起着至关重要的作用。我们得出的结论是，量身定制的“类静脉”纳米通道结构可用作未来核反应堆的先进耐辐射材料。