锆化氢表面MAO/ZrO?-Y?O?复合涂层的微观结构优化与阻氢机制

Microstructure optimization and hydrogen barrier mechanism of MAO/ZrO2-Y?O? composite coatings on zirconium hydride

摘要:

本研究通过结合微弧氧化（MAO）与溶胶-凝胶技术，在锆氢ZrH1.8基体表面成功制备了复合MAO/ZrO?-Y?O?氢阻涂层。系统研究了Y?O?含量（0-16 mol%）和热处理温度（300-600°C）对涂层微观结构、相组成及氢阻性能的影响。结果表明，当Y?O?含量为12 mol%时，复合涂层性能最优：孔隙率低至2.9%，氧化锆四方相（t-ZrO?）含量达18.32%，氢渗透降低因子（PRF）提升至19.3，氢损失温度升高至682°C。600°C热处理进一步优化了涂层的表面完整性和结晶度，并使氢损失温度升至686°C。涂层的氢阻机制归因于物理屏障、氧空位化学捕获与相稳定化的协同作用。

Abstract:

In this study, by combining micro-arc oxidation (MAO) and sol-gel technology, the composite MAO/ZrO?-Y?O? hydrogen barrier coatings were successfully prepared on the surface of ZrH1.8 zirconium hydride matrix. The effects of the content of Y?O? concentration (0-16 mol%) and heat treatment temperature (300-600°C) on the microstructure, phase composition, and hydrogen-blocking properties of the coatings were systematically investigated. The results showed that the composite coatings exhibited optimal performance when the Y?O? content was 12 mol%, the porosity was as low as 2.9%, the tetragonal phase of zirconia (t-ZrO?) content reached 18.32%, the hydrogen permeation reduction factor (PRF) was elevated to 19.3, and the hydrogen-loss temperature was increased to 682°C. The heat treatment at 600°C further optimized the surface integrity and crystallization of the coatings, and led to the increase of the hydrogen loss temperature to 686°C. The hydrogen barrier mechanism of the coatings was attributed to the synergistic effect of physical barrier, chemical trapping of oxygen vacancies and phase stabilization.