核反应堆在工业工程中发现的一些极端条件下运行,将强烈辐射通量与腐蚀性冷却剂和高温相结合。 反应堆芯、初级冷却系统和封存结构所使用的结构材料必须保持几十年的完整。 保护涂层是一条关键的防线,可以防止损坏的部件损害安全、增加维护成本或缩短工厂寿命。 在过去20年中,涂层技术从简单的腐蚀屏障发展到适合核环境的复杂的多功能系统。 本文审查了涂层材料和方法的最新创新、其好处和局限性,以及有可能为下一代核电厂提供更具有复原力的解决方案的研究方向。

核反应堆环境:对材料的需求设定

To appreciate the role of coatings, one must first understand the aggressive conditions inside a nuclear reactor. The primary coolant loop—whether light water, heavy water, or liquid sodium—carries heat away from the fuel assemblies but also promotes corrosion of metal surfaces. In water-cooled reactors, radiolysis produces oxidizing species like hydrogen peroxide, which accelerate general and localized corrosion. In sodium-cooled fast reactors, oxygen impurities and mass transport effects can cause corrosion and carburization. Meanwhile, high-energy neutron and gamma radiation induce displacement damage and transmutation within coating and substrate materials, altering their mechanical and chemical properties. Temperatures in pressurized water reactors (PWRs) reach around 320 °C, while in boiling water reactors (BWRs) they are slightly lower but still aggressive. Advanced reactors, such as very high-temperature reactors (VHTRs), push toward 900–1000 °C. The combination of thermal stress, radiation, and chemical attack demands coatings that can adhere firmly, maintain chemical stability, and self-