钼酸盐毒性低,有良好的缓蚀性能,可代替有毒的铬酸盐用于镁合金表面的耐蚀处理.采用正交试验优选了钼酸盐转化工艺中的Na2MoO4·2H2O浓度、NaH2PO4·2H2O浓度、pH值、成膜温度和时间,考察了压铸AZ91D镁合金在优化工艺条件下所得钼酸盐转化膜的耐蚀性能,利用扫描电子显微镜(SEM)、能谱仪(EDS)和中性盐雾腐蚀试验(NSS)等手段研究了转化膜的组成和形貌.结果显示:钼酸盐转化膜主要由Mg,Al,Mo,P和O等元素构成,膜层较为平整、均匀、致密,并存在一些不规则的微裂纹;钼酸盐转化膜有效地提高了AZ91D镁合金的耐蚀能力.
参考文献
| [1] | 杨旭,潘复生,赵华文,周晓霞,李欣.镁合金表面有机转化膜的制备及性能[J].材料保护,2009(01):5-7. |
| [2] | 陈祥,金华兰,杨湘杰,叶寒,吴丹,王明.镁合金磷酸盐、锡酸盐化学转化工艺及膜层耐蚀性研究[J].材料保护,2008(08):22-24. |
| [3] | Guangling Song;Sarath Hapugoda;David St John .Degradation of the surface appearance of magnesium and its alloys in simulated atmospheric environments[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2007(3):1245-1265. |
| [4] | Konno H;Narumi K;Habazaki H .Molybdate/Al (Ⅲ)composite films on steel and zinc-plated steel by chemical conversion[J].Corrosion Science,2002,44(08):1889-1900. |
| [5] | A.S. HAMDY;A.M. BECCARIA;P. TRAVERSO .Corrosion protection of AA6061 T6-10 percent Al_2O_3 composite by molybdate conversion coatings[J].Journal of Applied Electrochemistry,2005(5):467-472. |
| [6] | T. K. Rout;N. Bandyopadhyay .Effect of molybdate coating for white rusting resistance on galvanized steel[J].Anti-Corrosion Methods and Materials,2007(1):16-20. |
| [7] | D. E. Walker;G. D. Wilcox .Molybdate based conversion coatings for zinc and zinc alloy surfaces: a review[J].Transactions of the Institute of Metal Finishing: The International Journal for Surface Engineering and Coatings,2008(5):251-259. |
| [8] | LU Jin-tang,WU Hai-jiang,KONG Gang,CHE Chun-shan,XU Qiao-yu.Growth and corrosion behavior of rare earth film on hot-dip galvanized steel[J].中国有色金属学会会刊（英文版）,2006(06):1397-1401. |
| [9] | 杨熙珍;杨武.金属腐蚀电化学热力学:电位-pH图及其应用[M].北京:化学工业出版社,1991:201-204. |
| [10] | E. Klusmann;J. W. Schultze .pH-Microscopy: technical application in phosphating solutions[J].Electrochimica Acta,2003(20/22):3325-3332. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%