贫铀表面阴极微弧电沉积氧化铝涂层的研究

Study of Alumina Coating Deposited on Depleted Uranium Surface by Cathodic Microarc Method

摘要:

以1.0mol.L_-1Al(NO₃)₃.9H₂O的乙醇溶液为电解液,用阴极微弧电沉积的方法在贫铀表面制备出厚度约为65μm的氧化铝陶瓷涂层,通过扫描电子显微镜(SEM)观察了涂层的表面和截面形貌,通过X射线衍射仪(XRD)及X射线能量色散谱(EDS)分析了涂层的成分以及相组成,通过电化学综合测试系统分析了涂层的电化学腐蚀性能,结果表明：涂层表面粗糙多孔,与基体呈犬牙咬合状结合；涂层主要由α-Al₂O₃和γ- Al₂O₃组成；涂层中含有少量的U元素,表明膜/基界面附近的贫铀基体在微弧放电的作用下也参与了成膜；沉积氧化铝涂层后,样品的腐蚀电流密度降低了2个数量级,耐腐蚀性能得到大幅度提高。

Abstract:

An alumina coating with a thickness of 65μm was prepared on depleted uranium surface by cathodic microarc desposition in 1mol/L Al(NO₃)₃.9H₂O ethanol solution. The morphology, composition and phase constituent of alumina coating were analyzed by SEM, XRDand EDS. The corrosion resistance were determined by electrochemical integrated test system. The results show that the coating, which is composed of α-Al₂O₃and γ- Al₂O_3, remain a good adhesion to depleted uranium substrate. The coating contains a little uranium element, which confirms that depleted uranium substrate near the coating /uranium also takes part in the sintering process of coating under cathodic microarc discharge. The coating reduce the depleted corrosion current by two orders-of-magnitude, which shows the good corrosion resistance.