TMA对熔融盐中铝镀层结构及耐蚀性的影响  

EFFECT OF TMA ON STRUCTURE AND CORROSION RESISTANCE OF ALUMINUM COATINGS FROM MOLTEN SALT

作　　者：王小花[1] 杨占红[1] 李旺兴 陈建华 王升威[1] 李景威[1] 

机构地区：[1]中南大学化学化工学院,长沙410083 [2]中国铝业郑州研究院,郑州450041

出　　处：《中国腐蚀与防护学报》2009年第5期360-364,共5页Journal of Chinese Society For Corrosion and Protection

基　　金：国家科技支撑项目(2006BAE03B03)

摘　　要：在摩尔比为0.66:0.17:0.17的AlCl_3-NaCl-KCl共融盐中添加表面活化剂四甲基氯化铵(TMA),接通直流电在铁片上获得了Al镀层。用扫描电子显微分析、X射线衍射分析和极化曲线等技术测试镀层的表面形貌、相结构及耐腐蚀性能,并用循环伏安法研究添加TMA对Al电沉积机理的影响。研究表明,添加1.0 mass%TMA时,电镀电流效率高达93.6%;纯氯化物熔盐中所得Al晶粒呈针状,为(200)面高择优取向的面心立方结构,添加TMA后获得的Al晶粒细化且形状不规则,呈无序晶面取向。添加TMA后,Al镀层的点腐蚀电位提高了0.12 V,同时增加了电沉积反应的不可逆程度,利于Al在熔融盐中的电镀。With the presence of tetramethylammonium chloride the aluminum coatings were obtained on iron substrate in eutectic chloride molten salt by D.C. plating. Scanning electron microscope（SEM）, X-ray diffraction（XRD） and polarization curves were used to test the surface morphology, microstructure and corrosion resistance of the obtained coatings. Effect of tetramethylammonium（TMA） on A1 deposition mechanism in the molten salt was investigated by cyclic voltammogram. The results showed that optimum currency efficiency of 93.6% was obtained when mass fraction of TMA reached to 1.0%. Aluminum coatings obtained in eutectic chloride molten salt is acicular and has （200） preferred orientation face-centered cubic structure, while that obtained in TMA added molten salt is irregular. Pitting corrosion potential of aluminum coating was enhanced 0.12 V and the extent of irreversibility was enlarged by adding TMA.

关 键 词：四甲基氯化铵 AlCl3-NaCl-KCl熔融盐 铝镀层 晶体取向 耐蚀性 

分 类 号：TQ153.2[化学工程—电化学工业]