摘要
通过正交实验对Mg2Ni合金铈转化处理工艺进行了研究,结合扫描电子显微镜(SEM)、能量散射光谱(EDS)法分析了膜层的表面形貌,并利用Tafel极化曲线、电化学阻抗谱(EIS)等分析手段对膜层性能进行了测试,获得了室温下(25±5)℃最佳的成膜条件:Ce(NO3)3浓度为0.05 mol/L,p H值为4,镀膜时间为10 min,成膜促进剂的添加量为2m L/L。结果表明,采用以Ce(NO3)3为主要成分的酸性处理液,可以在Mg2Ni合金表面形成一层淡黄色的具有颗粒状突起的转化膜,膜层主要以Ce和O元素为主;经成膜溶液处理后,合金的自腐蚀电位由-943.419 m V正移到了-934.545 m V,合金与溶液表面的电荷转移阻抗值从0.174 9Ω提高到了0.187 3Ω,经过20个放电循环,合金的放电保持率由12.9%提高到了70%,说明铈转化处理可提高Mg2Ni合金的耐腐蚀性能,较好地改善合金的循环稳定性。
The process of cerium conversion coating on Mg2 Ni alloy was stydied by using orthogonal layout. The coating surface morphology and composition and the coating performance were tested by using the ways of SEM, EDS,Tafel polarization curve, EIS and so on. While the concentration of Ce（NO3）3was 0.05 mol/L, the p H was 4, the treatment time was 10 min and the addition of coat-acceleration agent was 2 m L/L, the best coating would be formed at room temperature（25±5）℃. The results show that a layer of light yellow conversion coating with granular protuberances can be formed. The coating elements mainly were O and Ce. After treated by the coat-forming solution, the corrosion potential and the surface charge transfer resistance were both significantly improved. And after 20 dischare cycles, the alloy dischare retentionrate was increased substantially. The cycle stability was improved better.
出处
《电源技术》
CAS
CSCD
北大核心
2015年第3期498-501,共4页
Chinese Journal of Power Sources
基金
国家自然科学基金(50961009)
