锆合金耐事故燃料包壳涂层研究进展

Research Progress in Zirconium Alloy for Accident Tolerant Fuel Cladding Coating

摘要:

日本福岛核事故后，以提升反应堆在事故工况下的稳定性和安全性为目的的事故容错燃料技术研究已成为世界范围内的研究热点。涂层技术是事故容错燃料项目短期规划主要的发展方向。在锆合金燃料包壳表面制备保护性涂层能够在不改变现有燃料体系结构的前提下，提升锆合金包壳在反应堆失水事故条件下的事故容错能力。本文综述了国内外锆合金包壳涂层领域研究成果，总结了锆合金表面涂层的种类、性能、制备技术及应用前景，结合涂层的制备技术，综合分析了各种制备方法的特点以及未来需集中要解决的问题。在此基础上，提出金属Cr涂层具有良好的耐腐蚀性能，尤其是在>1200°C高温蒸汽腐蚀条件下能够有效保护锆合金基体，是目前最有希望工程化应用的事故容错涂层。同时，探索适合于工程化应用的Cr涂层制备技术，解决Cr涂层的制备缺陷，提升涂层的结构致密性以及界面性能是目前亟待解决的关键问题。

Abstract:

After the Fukushima nuclear accident in Japan, the world-wide research is focused on the accident tolerant fuel (ATF) program, aimed to enhance the stability and safety of nuclear reactor under normal or off-normal conditions. In the short-term-plan of ATF program, coating technology is considered as a revolutionary approach. Synthesizing a protective coating on the surface of Zr based cladding would improve oxidation resistance obviously with minimal effect on structure of the existing fuel system and properties of the existing nuclear Zr based materials. In this study, a review of coating development status based on Zr alloy is offered, including the coating types, properties and application prospects，also the characteristics of synthesization technology. Based on these analyses, it’s believed that Cr coating could be considered as the best candidate ATF material for industrial application at present, due to its good corrosion resistance at high temperature steam, especially higher than 1200℃. At the same time, it is a key problem to explore a Cr coating synthesization technology suitable for engineering application, with none structure defects, more density and higher interface performance.