摘要
为了提高6A16铝合金的耐蚀能力,实现对微弧氧化涂层微观组织结构与成分的精确调控,采用微弧氧化技术及水热法在6A16铝合金表面制得TiC/MAO复合涂层,并通过试验测试方法对制备参数进行优化,获得了水热法制备复合膜的最优参数为:溶液pH值8,反应时间24 h,反应温度180℃。当pH=8时形成了致密的TiC膜,试样达到了最低的腐蚀电流、最大的腐蚀电位,表现出优异的耐蚀能力。将反应时间增至24 h时,在试样表面形成了更多的水滑石,只形成了颗粒状的外形,并未形成片状结构。此时达到了更小的腐蚀电流,同时腐蚀电位进一步提升,获得了更优的耐蚀能力。提高反应温度至180℃后,在试样表面产生了更多的TiC,获得了致密的TiC组织,形成了明显的片层外形特征,微孔数也发生了减小,此时表现出优异的钝化性能,腐蚀电流也很低。
In order to improve the corrosion resistance of 6A16 aluminum alloy and realize the accurate regulation of micro-structure and composition of micro-arc oxidation coating,the TiC/MAO composite coating was prepared on the surface of 6A16 aluminum alloy by micro-arc oxidation technology and hydrothermal treatment,and the preparation parameters were optimized by experimental test method.Results showed that the optimal parameters for the preparation of composite coating by hydrothermal method were as follows:the pH value of the solution was 8,the reaction time was 24 h,and the reaction temperature was 180℃.When pH value of solution was 8,a dense TiC film was formed,and the sample had the minimum corrosion current and the maximum corrosion potential,showing excellent corrosion resistance.When the reaction time increased to 24 h,more hydrotalcite was formed on the surface of the sample in a granular shape,not a flake structure.At this time,a smaller corrosion current was obtained and the corrosion potential was further increased,indicating better corrosion resistance.When the reaction temperature raised to 180℃,more TiC was generated on the sample surface,which resulted in the formation of a dense TiC structure,obvious laminar appearance characteristics,and a decrease in the number of micropores.At this time,excellent passivation performance was obtained,and the corrosion current was also low.
作者
于志刚
王亮亮
王小龙
YU Zhi-gang;WANG Liang-liang;WANG Xiao-long(College of Automotive Engineering,Chengdu Industrial Vocational and Technical College,Chengdu 610213,China;Chongqing Automotive Power System Test Engineering Technology Research Center,Chongqing 401120,China;School of Mechanical Engineering,Chengdu University,Chengdu 610106,China)
出处
《材料保护》
CAS
CSCD
2021年第8期109-113,126,共6页
Materials Protection
基金
四川省科技计划项目(20KPZP0014)资助。
