中文摘要：

采用恒压模式分别在不同浓度Na2SiO3电解液体系下对ZrH1.8表面进行微弧氧化处理,利用X射线衍射（XRD）仪、扫描电子显微镜（SEM）、膜层测厚仪测试了陶瓷层的相结构、表面形貌、截面形貌及厚度,通过真空脱氢实验评估了陶瓷层的阻氢性能。研究结果表明：当Na2SiO3浓度在6~14 g/L变化时,陶瓷层的厚度在25~61μm范围内。随着Na2SiO3浓度的增加,电解液的电导率线性增大,微弧氧化陶瓷层厚度逐渐减小。氢化锆表面微弧氧化陶瓷层由致密层和疏松层构成,靠近基体一侧为致密层,陶瓷层外层为疏松层,在疏松层中存在空洞和裂纹缺陷。陶瓷层由单斜相氧化锆（M-ZrO2）和四方相氧化锆（T-ZrO1.88）构成,且以单斜相氧化锆（M-Zr O2）为主,随着电解液中Na2SiO3浓度的增加,四方相T-ZrO1.88在陶瓷层中比例增大。综合比较,在Na2SiO3浓度为8 g/L的电解液体系下可以获得厚度适中,表面平整,致密性较好,阻氢性能优异的陶瓷层,陶瓷层的PRF值达到最大值10.8。

英文摘要：

Micro-arc oxidation（MAO） process under constant voltage mode was conducted on zirconium hydride in different Na2 Si O3-concentration electrolyte systems. The surface and cross-sectional morphologies, phase structures and the thicknesses of the oxide layers were characterized by scanning election microscopy（SEM）, X-ray diffraction（XRD） and film thickness gauges, respectively. Hydrogen resistance performance of the oxide layers were evaluated by the method of vacuum dehydrogenation. The results indicate that thicknesses of the oxide layers on the surface of zirconium hydride changes from 25 μm to 61 μm when Na2 Si O3 concentration varies from 6 g/L to 14 g/L. The thickness of the oxide layer decreases and the electric conductivity increases lineally with increasing of Na2 Si O3concentration. The oxide layer is composed of outer loose layer and inner compact layer. Holes and cracks exist in loose layer. The oxide layers are mainly composed of M-Zr O2 and T-Zr O1.88 and the amount of T-Zr O1.88 increases with increasing of Na2 Si O3 concentration. The oxide layer formed in silicate electrolyte system with 8 g/L Na2 Si O3 is compact, uniform and the thickness is moderate, which exhibits an excellent hydrogen permeation resistance. The PRF（permeation reduction factor） value of the oxide layer reaches up to the maximum value of 10.8 when Na2 Si O3 concentration of the silicate electrolyte system is 8 g/L.