锌钙系复合磷化膜的制备及其对16Mn钢腐蚀防护性能的影响  

Preparation of zinc-calcium composite phosphating films and its effect on the corrosion protection performance of 16Mn steel

作　　者：张翼 杨滔[2] Zhang Yi;Yang Tao(Xi'an Anju Construction Management Co.,Ltd,Xi'an 710000,China;School of Architecture,Tsinghua University,Beijing 100084,China)

机构地区：[1]西安市安居建设管理集团有限公司,陕西西安710000 [2]清华大学建筑学院,北京100084

出　　处：《电镀与精饰》2024年第8期1-10,共10页Plating & Finishing

基　　金：国家重点研发计划项目(2022YFC3800600)。

摘　　要：通过磷酸盐沉淀结晶过程将聚四氟乙烯(PTFE)颗粒引入锌钙系磷化膜中获得锌钙系复合磷化膜,并研究PTFE颗粒分散液添加量和搅拌速度对锌钙系磷化膜的微观形貌、化学组成、PTFE颗粒含量、厚度以及对16Mn钢的腐蚀防护性能的影响。结果表明:改变PTFE颗粒分散液添加量或搅拌速度制备的不同锌钙系复合磷化膜晶粒大小较均匀,但是呈散乱无序状堆积,PTFE颗粒附着在晶粒表面并填补晶粒间孔洞,起到阻挡腐蚀介质并阻碍腐蚀反应的作用,明显提高锌钙系复合磷化膜的耐腐蚀性能。当搅拌速度为300 r/min时,添加25 mL/L PTFE颗粒分散液制备的锌钙系复合磷化膜晶粒表面附着较多PTFE颗粒,并且颗粒呈较均匀分散状态很好的填补晶粒间孔洞。该复合磷化膜含有Zn、Ca、P、O、C和F元素,PTFE颗粒的含量和厚度分别达到4.1%、12.4μm,具有最高的电荷转移电阻8528Ω·cm^(2)和低频阻抗值6015Ω·cm^(2),表现出优异的耐腐蚀性能,使16Mn钢的腐蚀防护性能明显优于常规锌钙系磷化膜。Zinc-calcium composite phosphating film was obtained by introducing PTFE(PTFE)particles into the zinc-calcium phosphating film through the process of phosphate precipitation and crystallization,and the effect of addition amount of PTFE particles dispersion solution and stirring speed on the microstructure,chemical composition,content of PTFE particles and thickness of the composite phosphating film and the corrosion protection performance of composite phosphating film on 16Mn steel were investigated.The results show that the different zinc-calcium composite phosphating films prepared by changing the addition amount of PTFE particles dispersion solution or stirring speed have uniform grain size,but they are scattered and disordered,and PTFE particles adhere to the grain surface and fill the pores between the grains,which can block the corrosive medium and hinder the corrosion electrochemical reaction,and obviously improve the corrosion resistance of zinc-calcium composite phosphating film.When the stirring speed is 300 r/min and adding amount of PTFE particles dispersion solution is 25 mL/L,many PTFE particles attached to the surface of the grains of the zinc-calcium composite phosphating film and the particles are evenly dispersed to fill the pores between the grains.The composite phosphating film contains Zn,Ca,P,O,C and F elements,the content of PTFE particles and thickness reach 4.1% and 12.4μm,respectively,and has the highest charge transfer resistance 8528Ω·cm^(2) and low-frequency impedance value 6015Ω·cm^(2),showing excellent corrosion resistance.The corrosion protection performance of the zinc-calcium composite phosphating film prepared under the above condition on 16Mn steel is obviously better than that of con-ventional zinc-calcium phosphating film.

关 键 词：锌钙系复合磷化膜 16MN钢 PTFE颗粒分散液 搅拌速度 腐蚀防护性能 

分 类 号：TG174[金属学及工艺—金属表面处理]