锰酸盐铝管表面处理技术研究  

A Research on Manganate Surface Treatment of Aluminum Tubes

作　　者：秘雪 满瑞林[1] 李波[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《湖南工业大学学报》2017年第4期65-70,共6页Journal of Hunan University of Technology

基　　金：湖南省科技重大专项基金资助项目(2010FJ1011);湖南省科技计划基金资助项目(2016TP1007)

摘　　要：研究了无铬钝化铝管处理技术,即利用锰酸盐表面处理技术制备铝管钝化膜,锰酸盐的配方为10 g/L KMnO_4+20 g/L Na_2HPO_4+1.0 g/L KF,调节溶液pH值为9.5;其处理工艺为60℃条件下处理10min。并用硫酸铜点滴实验、海水腐蚀实验、碱浸实验对制备的铝管锰酸盐钝化膜与铬酸盐钝化膜、空白样进行对比实验,结果表明,铝管表面的锰酸盐钝化膜显著提高了铝管的耐蚀性能,其耐蚀效果超过了常规的铬酸盐钝化膜。电化学Tafel极化曲线测试结果表明:锰酸盐钝化膜的存在使得铝的自腐蚀电位明显正移,自腐蚀电流密度显著下降,从而有效降低了铝管腐蚀速率。A non-chrome treatment technology has been developed,with 10 g/L KMnO_4＋20 g/L Na_2HPO_4＋1.0 g/L KF,with 9.5 the solution pH,with 10 min the processing time,and 60 ℃ the processing temperature.A comparison has been made between the test results of the copper sulfate experiment,seawater corrosion experiment and alkali leaching experiment for the preparation of manganese oxide passivation films and chromate passivation films.The results show that manganate passivation films help to significantly improve the corrosion resistance of aluminum tubes,with a better performance in this aspect than that of conventional chromate passivation films.And experiments conducted on the electrochemical Tafel polarization curves indicate that the existence of manganate passivation films helps to make the corrosion potential of Al shift positively,thus reducing the corrosion current density significantly and decreasing the corrosion rate of Al effectively.

关 键 词：耐蚀性能 铝管 锰酸盐钝化膜 钝化 

分 类 号：TG178[金属学及工艺—金属表面处理]