阳极氧化钽酸锂薄膜在NaOH溶液中的腐蚀行为研究  

Corrosion Behavior of Anodic Oxide LiTaO3 Thin Film in NaOH Solution

作　　者：胡立坤 谢盼平 袁思成 许登峰 彭智 谢阿禧 郑峰[1] HU Likun;XIE Panping;YUAN Sicheng;XU Dengfeng;PENG Zhi;XIE Axi;ZHENG Feng(School of Materials Science and Engineering, Central South University, Changsha 410083, China;Changsha South Tantalum Niobium Co., Ltd., Changsha 410083, China;Second Middle School of Yongxing County, Chenzhou 423301, China)

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]长沙南方钽铌有限责任公司,长沙410083 [3]永兴二中,郴州423301

出　　处：《腐蚀科学与防护技术》2019年第4期379-386,共8页Corrosion Science and Protection Technology

摘　　要：通过阳极氧化法在高纯钽片表面制备了钽酸锂复合薄膜,采用浸泡失重法和电化学测试法考察了镀膜前后样品在10%(质量分数) NaOH溶液中的腐蚀行为。利用X射线衍射仪、扫描电子显微镜及能谱仪分别对薄膜的物相组成、表面及截面形貌、膜层厚度进行了测试分析。结果表明,阳极氧化后得到的复合薄膜由钽酸锂和氧化钽组成;该薄膜与基体之间结合良好,厚度约3μm;镀膜后样品的质量腐蚀速率至少减少了6倍,腐蚀电流密度下降了2个数量级,腐蚀96 h后样品表面没有明显变化。而对比的纯钽样品却发生了严重的腐蚀反应,生成了很多长条状和多棱柱状的腐蚀产物Na3TaO4、Na2Ta2O6和Na8Ta6O19。Lithium tantalate(LiTaO3) thin film was synthesized on high purity tantalum foil in molten LiNO3 via anodic oxidation. Then corrosion behavior of the LiTaO3 coated Ta foil was studied in 10%(mass fraction) NaOH solution by means of immersion corrosion test and electrochemical measurement. While the LiTaO3 coated Ta foil before and after corrosion test was characterized with X-ray diffractometer(XRD), scanning electron microscopy(SEM) and energy dispersive spectrometer(EDS), respectively. Results showed that the anodic oxidation thin film consists of LiTaO3 and tantalum oxides. The film was 3 μm in thickness and well bounded to the Ta matrix. The corrosion rate of the anodic oxidation thin film coated Ta foil was 1/6 that of the plain Ta foil, correspondingly, the corrosion current density of the former was two order magnitude lower than that of the later. Moreover, the morphology of the anodic oxidation thin film coated Ta foil remains unchanged even after 96 h immersion test. In contract, the plain Ta foil underwent severely corrosion with formation of rod-like and prism-like corrosion products of Na3TaO4, Na2Ta2O6 and Na8Ta6O19.

关 键 词：钽酸锂薄膜 阳极氧化 NAOH溶液 腐蚀行为 

分 类 号：TG174[金属学及工艺—金属表面处理]