State Key Laboratory of Nuclear Physics and Technology, Department of Technical Physics, School of Physics, Peking University, Beijing, People's Republic of China.
Beijing Advanced Innovation Centre for Materials Genome Engineering, State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing, People's Republic of China.
Nat Mater. 2023 Apr;22(4):442-449. doi: 10.1038/s41563-022-01260-y. Epub 2022 May 30.
Materials capable of sustaining high radiation doses at a high temperature are required for next-generation fission and future fusion energy. To date, however, even the most promising structural materials cannot withstand the demanded radiation environment due to irreversible radiation-driven microstructure degradation. Here we report a counterintuitive strategy to achieve exceptionally high radiation tolerance at high temperatures by enabling reversible local disordering-ordering transition of the introduced superlattice nanoprecipitates in metallic materials. As particularly demonstrated in martensitic steel containing a high density of B2-ordered superlattices, no void swelling was detected even after ultrahigh-dose radiation damage at 400-600 °C. The reordering process of the low-misfit superlattices in highly supersaturated matrices occurs through the short-range reshuffling of radiation-induced point defects and excess solutes right after rapid, ballistic disordering. This dynamic process stabilizes the microstructure, continuously promotes in situ defect recombination and efficiently prevents the capillary-driven long-range diffusion process. The strategy can be readily applied into other materials and pave the pathway for developing materials with high radiation tolerance.
需要能够在高温下承受高辐射剂量的材料，以用于下一代裂变和未来的聚变能源。然而，迄今为止，即使是最有前途的结构材料，也由于不可逆转的辐射驱动微观结构退化，无法承受所需的辐射环境。在这里，我们报告了一种反直觉的策略，通过在金属材料中引入的超晶格纳米沉淀物实现可恢复的局部无序-有序转变，从而在高温下实现异常高的辐射耐受性。特别在含有高密度 B2 有序超晶格的马氏体钢中得到证实，即使在 400-600°C 的超高剂量辐射损伤后，也未检测到空洞肿胀。高度过饱和基体中超晶格的重排过程是通过辐射诱导点缺陷和过剩溶质的短程重新排列来实现的，这一过程发生在快速的弹道无序之后。这个动态过程稳定了微观结构，持续促进了原位缺陷复合，并有效地阻止了毛细管驱动的长程扩散过程。该策略可以很容易地应用于其他材料，并为开发具有高辐射耐受性的材料铺平道路。
