间隙元素协同作用下的氢化锆阻氢层界面扩散和生长机制研究

Researches on hydrogen permeation barrier for stainless steel matrix reveal that Al2O3, TiC, TiN and SiC show good hydrogen barrier effects, and the mechanism of antipermeation of hydrogen is the formation of C-H, N-H and O-H bonds. Researches on the hydrogen permeation barrier for zirconium hydride by in-situ oxidation show that the ZrO2 surface film is composed of outer loose layer with many cracks and inner dense layer, and further researches should be done to improve the properties of the dense layer and to eliminate the cracks of the loose layer..To improve the properties of dense layer, the idea of introducing C and N into the ZrO2 film is proposed to achieve a synergistic effect of C, N and O on hydrogen retention. To eliminate the cracks in the outer layer of in-situ oxide film, the idea of investigating the influence of oxygen source and oxygen potential on the structure of ZrO2 film is put forward. The contents of this project include: (1) the interaction and difussion mechanism of C, N and O in the film under different oxygen potential; (2) the diffusion mechanism of hydrogen in the multicomponent composite hydrogen permeation barrier; (3) the microstructure and phase structure of the multicomponent composite hydrogen permeation barrier; and (4) the effect of oxygen potential and sources on in-situ oxide film formation on the zirconium hydride substrate. The expected achievments are the formation mechanism of multicomponent composite ZrO2 film, the hydrogen retention mechanism of of multicomponent composite ZrO2 film, and the influence of of oxygen potential on the growth and evolution of ZrO2 film on the zirconium hydride substrate.

国内外对不锈钢基体阻氢膜研究表明Al2O3、TiC、TiN、SiC阻氢效果好，其阻氢机理是氢与膜层中的间隙元素形成了C-H、N-H、O-H键。对氢化锆表面阻氢膜的研究表明，原位氧化法获得的ZrO2阻氢膜由裂纹较多的外层和连续致密的内层构成，提高致密层性能和消除表面层裂纹是两个待解决的问题。.本项目提出在氧化锆膜中加入C、N，达到C、N、O协同阻氢效果；针对原位氧化膜表层存在较多裂纹缺陷问题，提出通过氧源和氧势的设计改善阻氢膜组织结构思路。本项目拟开展：(1)不同氧势条件下，C、N、O向膜内扩散的相互作用及扩散机制研究，(2)H在多元复合阻氢膜中向外扩散的扩散机制研究，(3)多元复合阻氢膜的组织形貌和相结构特征研究，(4)不同氧源条件下，氧势对氢化锆阻氢膜形成的影响规律研究。预期获得多元复合氧化锆膜形成机理和C、N、O协同阻氢机理，掌握氧势对氢化锆表面氧化锆阻氢膜生长影响规律。

氢化锆是可移动核反应堆电源堆芯关键材料，阻氢渗透涂层是关键技术之一，具有军民两用前景。.研究了二氧化碳、尿素、氮气等不同气源作用下，和有机硅溶胶作用等条件下阻氢膜制备方法，采用SEM/EDS、XRD、AES、XPS等手段对膜层性能进行了表征，研究了膜层生长规律和阻氢机理。表明有机硅溶胶可在氢化锆表面生成表面保护层，具有降低界面氧势、阻止氧向界面扩散的作用，有利于保证膜层性能。以尿素、氮气作为原位制膜原料，膜层主要成分为C、N、O、Zr，膜层由M-ZrO2、T-ZrO2、ZrN、ZrO、ZrC、ZrNO、ZrN0.36H0.8等化合物构成。H-O、H-N键具有阻止氢迁移的作用，膜层中的各种化合物中的C、N、O互相制约，具有阻止H-O键、H-N键移动的作用。磷调控阻氢渗透膜厚（μm）随时间（day）增长变化、氢渗透速率随时间变化符合Wagner模型，呈抛物线规律。成果应用于空间堆地面实验堆设计研究。.项目研究获得授权发明专利3项，发表SCI、EI收录论文14篇，获得2020年中国有色金属工业科学技术奖一等奖。