LY12铝合金的锰酸盐导电化学转化膜制备与表征  

Preparation and Characterization for Permanganate Chemical Conversion Film on LY12 Aluminum Alloy

作　　者：吴友恒[1] 黎学明[1] 杨文静[1] 高丽[1] 

机构地区：[1]重庆大学化学化工学院,重庆400044

出　　处：《表面技术》2011年第1期81-85,共5页Surface Technology

摘　　要：以KMnO4为主盐,Na2ZrF6作促进剂,研究了LY12铝合金锰酸盐化学转化膜的制备工艺,采用点滴法和膜接触电阻法评价转化膜的耐蚀性和导电性,并用SEM,EDS和XRD表征转化膜的形貌与组成,进而探讨成膜机理。结果表明:当KMnO4的质量浓度为5 g/L,Na2ZrF6的质量浓度为0.05 g/L,pH值2.0,温度65℃,转化时间60 s、沸水后处理30 min时,所制备的锰酸盐转化膜颜色呈金黄色,该膜层均匀、致密,主要成分为Al,O,Mn元素,由铝和锰的氧化物组成。LY12铝合金表面的锰酸盐化学转化膜耐蚀性和导电性明显提高,点滴法耐腐蚀时间达到57 s,转化膜表面接触电阻仅为铝合金基体接触电阻的15.6%。Prepartion technology of promanganate chemical anversion film on LY12 alaminum alloy was studied with main salt KMnO4 and accelerator Na2ZrF6.The corrosion resistance and conductivity of conversion film were tested by the dropping test and the contact resistance method,respectively.The film morphology,composition and structure were analyzed by SEM/EDS and XRD.A possible formation mechanism for permanganate conversion film was proposed.The results show that the best component of chemical conversion bath is 5 g/L KMnO4 and 0.05 g/L Na2ZrF6,while the pH value is 2.0 at 65 ℃ for 60s and the time of post treatment is 30 min in boiling water.The layer is uniform and compact,which is composed of Al,O,Mn elements.The corrosion resistance and conductivity of the conversion film increase obviously.The time of corrosion resistance is 57 seconds and the contact resistance of the conversion film is just 15.6% of the unconverted aluminum alloy.

关 键 词：铝合金 锰酸盐 转化膜 耐蚀性 导电性 

分 类 号：TG174.451[金属学及工艺—金属表面处理]