铝合金表面氟硅酸盐转化新工艺  

Novel fluorosilicate conversion process on aluminum alloys

作　　者：房新建[1] 郭瑞光[1] 张力[1] 王娜娜[1] 

机构地区：[1]西安建筑科技大学环境与市政工程学院,陕西西安710055

出　　处：《电镀与涂饰》2012年第5期37-40,共4页Electroplating & Finishing

基　　金：国家自然科学基金项目(20976143);教育部高等学校博士学科点专项科研基金(20096120110007)

摘　　要：以6063铝合金为基体,在由氟硅酸盐和氟化铵组成的转化液中制得无铬转化膜。以168h盐雾试验后试样未腐蚀面积分数为指标,研究了转化液组成和工艺条件对氟硅酸盐转化膜耐蚀性的影响。优化后氟硅酸盐转化的工艺参数为:Na2SiF63～5g/L,NH4F5～7g/L,pH5.5～6.5,温度25～35°C,转化时间12～16min。经氟硅酸盐处理后,铝合金表面得到由F、Al、Na、O和Si组成的、致密的无铬转化膜,铝合金的自腐蚀电位显著正移,耐蚀性提高。A chromium-free conversion coating was prepared from a conversion solution containing fluorosilicate and ammonium fluoride on 6063 aluminum substrate. The un-corroded area fraction of samples after salt spray test for 168 h were served as the standard to study the effect of the composition of conversion solution and process parameters on the corrosion resistance of fluorosilicate conversion coating. The optimized process parameters of fluorosilicate conversion are as follows： Na2SiF6 3-5 g/L, NH4F 5-7 g/L, temperature 25-35 ℃, pH 5.5-6.5, and conversion time 12-16 min. Compact chromium-free conversion coating containing F, Al, Na, O, and Si is obtained on the surface of aluminum by fluorosilicate conversion treatment. The corrosion resistance of aluminum is improved as evidenced by the positive shift of self-corrosion potential.

关 键 词：铝合金 氟硅酸盐 转化膜 耐蚀性 

分 类 号：TQ153.6[化学工程—电化学工业]