Study of a New Chromium-Free Conversion Coating Formed on ZnAl Alloy

查看全文 作　　者：LONGJin-ming GUOZhong-cheng HANXia-yun [1]YANGNing 机构地区：[1]FacultyofMaterialsandMetallurgicalEngineering,KunmingUniversityofScienceandTechnology,Kunming,China 出　　处：《材料热处理学报》索引2004年第25卷第05B期,共5页 摘　　要：A new chromium-free conversion film was obtained on surface of a ZnAl alloy by chemical conversion process. Influence of the additives in treating solution containing cerium salt on the corrosion protection of the conversion film formed on zinc alloy was investigated. Corrosion tests and electrochemical measurements in sodium chloride solution were performed . The microstructure and composition of the coatings were examined by means of SEM, EDS and XRD. It was found that the corrosion protection capabilities of the conversion film are markedly increased with the cerium nitride plus additives (hydrogen fluoride acid and an organic inhibitor) treating process. The modified conversion film is an organic/inorganic composite coating and is much more corrosion resistant than the conventional chromate conversion coating and the single cerium conversion coating. 关 键 词：ZnAl合金 铬自由转化涂层 稀土盐 有机抑制剂 防腐蚀