柠檬酸对建筑用16Mn钢磷化膜物相与耐蚀性的影响  

Effect of Citric Acid on Phase and Corrosion Resistance of Phosphating Films on 16Mn Steel for Construction

作　　者：张伟华[1] 张颖超 孙伟[1] 赵铭涛 赵刚[1] ZHANG Weihua;ZHANG Yingchao;SUN Wei;ZHAO Mingtao;ZHAO Gang(Qingdao Huanghai University,Qingdao 266427,China)

机构地区：[1]青岛黄海学院,山东青岛266427

出　　处：《电镀与精饰》2022年第6期21-25,共5页Plating & Finishing

基　　金：青岛黄海学院校级科研项目(2019KJ04)。

摘　　要：向磷化液中添加柠檬酸,采用浸渍法在建筑用16Mn钢表面制备磷化膜,并研究了柠檬酸浓度对磷化膜物相、形貌与耐蚀性的影响。结果表明:添加不同浓度柠檬酸制备的5种磷化膜都由Zn_(3)(PO_(4))_(2)·4H_(2)O和Zn_(2)Fe(PO_(4))_(2)·4H_(2)O相组成,但5种磷化膜的形貌和耐蚀性存在一定差异。随着柠檬酸浓度从1 g/L增加到4 g/L,磷化膜表面平整度和致密性先逐步改善然后降低,阻抗模值和相位角都呈现先增大后减小的趋势。当柠檬酸浓度为2 g/L时,磷化膜结晶较均匀致密,平整度较好,阻抗模值和最大相位角分别达到2819Ω·cm^(2)、58.4°,该磷化膜能够有效提高16Mn钢的耐蚀性。而当柠檬酸浓度过高时,会抑制成膜过程,导致磷化膜表面平整度和致密性降低,耐蚀性明显下降。Phosphating films were prepared on 16Mn steel for construction by impregnation method from the phosphating solution containing citric acid,and the effect of the concentration of citric acid on the phase,morphology and corrosion resistance of phosphating films was studied.The results showed that five phosphating films prepared by adding different concentration of citric acid had the same phase,which was composed of Zn_(3)(PO_(4))_(2)·4H_(2)O and Zn_(2)Fe(PO_(4))_(2)·4H_(2)O.However,the morphology and corrosion resistance of five phosphating films were different.With the increase of the concentration of citric acid from 1 g/L to 4 g/L,the surface flatness and compactness of phosphating film were gradually improved first and then decreased,and the impedance modulus and phase angle were increased first and then decreased.When the concentration of citric acid was 2 g/L,the phosphating film was uniform and compact,and the impedance modulus and the maximum phase angle reached 2819Ω·cm^(2) and 58.4°,respectively,which can effectively improve the corrosion resistance of 16Mn steel.However,when the concentration of citric acid was too high,the film forming process will be inhibited and the surface flatness and compactness of the phosphating films reduced,resulting in significantly decline of corrosion resistance.

关 键 词：物相 耐蚀性 磷化膜 柠檬酸 

分 类 号：TB43[一般工业技术]