法兰磷化处理及锌系磷化膜的耐腐蚀性能研究  

Study on Phosphating Treatment of Flange and Corrosion Resistance of Zinc Phosphating Film

作　　者：刘艳 冀杰[2] LIU Yan;JI Jie(Department of Mechanical Electrical Engineering,Henan Vocational College of Water Conservancy and Environment,Zhengzhou 450008,China;CET-College of Engineering and Technology,Southwest University,Chongqing 400715,China)

机构地区：[1]河南水利与环境职业学院机电工程系,郑州450008 [2]西南大学工程技术学院,重庆400715

出　　处：《有色金属工程》2021年第5期12-17,共6页Nonferrous Metals Engineering

基　　金：国家自然科学基金资助项目(61304189);河南省职业教育教学改革研究项目(JG1908)。

摘　　要：以提高45#钢法兰的耐腐蚀性能为目标,使用含有硝酸镨的锌系磷化液对法兰进行磷化处理,并研究了硝酸镨的质量浓度对磷化处理后的法兰宏观形貌以及锌系磷化膜的微观形貌和耐腐蚀性能的影响。结果表明:硝酸镨对磷化处理后的法兰宏观形貌基本无影响,但在不同硝酸镨质量浓度下获得的磷化膜微观形貌存在差异,导致磷化膜的耐腐蚀性能发生改变。随着硝酸镨浓度从0 g/L增加到4.0×10^(-2) g/L,磷化膜的平整度和致密度逐步改善,耐腐蚀性能明显提高。随着硝酸镨质量浓度从4.0×10^(^(-2)) g/L增加到6.0×10^(-2) g/L,磷化膜的平整度和致密度转而变差,导致耐腐蚀性能下降。硝酸镨质量浓度为4.0×10^(-2) g/L时获得的磷化膜结晶更致密,其电荷转移电阻、频率为0.01 Hz时的阻抗模值以及液滴变色时间均最大,分别达到2150Ω·cm^(2)、2744Ω·cm^(2)、150 s,该磷化膜表现出良好的耐腐蚀性能。Phosphating treatment of 45#steel flange was carried out using the zinc phosphating solution containing praseodymium nitrate in order to improve its corrosion resistance,and the influence of the mass concentration of praseodymium nitrate on the macro-morphology of flange after phosphating treatment,the micro-morphology and corrosion resistance of zinc phosphating films were studied.The results show that praseodymium nitrate has no obvious effect on the macro-morphology of flange after phosphating treatment,but there are certain differences in the micro-morphology of the phosphating films obtained with different mass concentration of praseodymium nitrate,which leading to changes in the corrosion resistance of phosphating films.As the mass concentration of praseodymium nitrate increased from 0 g/L to 4.0×10^(-2)g/L,the flatness and compactness of phosphating film were gradually improved,and the corrosion resistance was significantly improved.However,as the mass concentration of praseodymium nitrate increased from 4.0×10^(-2)g/L to 6.0×10^(-2)g/L,the flatness and compactness of phosphating film became worse,which leading to a decline in corrosion resistance.When the mass concentration of praseodymium nitrate was 4.0×10^(-2)g/L,the phosphating film obtained has finer crystals and maximum charge transfer resistance,when the frequency was 0.01 Hz and discoloration time of droplet,resistance values were 2150Ω·cm^(2),2744Ω·cm^(2),150 s respectively.The phosphating film exhibits better corrosion resistance than that of other phosphating films.

关 键 词：磷化处理 法兰 锌系磷化膜 耐腐蚀性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]