AZ91D镁合金耐蚀-导电磷化膜的制备及性能研究  

Preparation and Performance Research of Corrosion-resistant Conductive Phosphating Film on AZ91D Magnesium Alloy

作　　者：张书弟[1] 杨琳琳 席绢 张颜茹 ZHANG Shudi;YANG Linlin;XI Juan;ZHANG Yanru(Shenyang Ligong University,Shenyang 110159,China)

机构地区：[1]沈阳理工大学环境与化学工程学院,沈阳110159

出　　处：《沈阳理工大学学报》2020年第4期6-10,共5页Journal of Shenyang Ligong University

基　　金：国家自然科学基金面上项目(51771050)

摘　　要：为提高镁合金产品的性能和安全,以及在军事、电器和通信设备等邻域的应用,研究镁合金耐蚀-导电化学转化膜具有重大意义。在AZ91D镁合金表面采用锌系磷化液制备耐蚀-导电磷化膜,研究不同添加剂和不同质量浓度NaNO3对镁合金磷化膜性能的影响。利用SEM、EDS表征膜层表面形貌及元素组成,利用电化学工作站及高锰酸钾点滴液测试膜层icorr和点滴时间判断耐蚀性能,利用数字万用表测试膜层表面接触电阻判断导电性能。结果表明:加入1g/L硝酸钙时,磷化膜均匀完整且icorr由44.5μA/cm2减小为19.7μA/cm2,再加入60g/L NaNO3后磷化膜均匀致密且镁合金β相上膜层较薄,膜层高锰酸钾点滴时间为16.5s并且表面接触电阻能达到200mΩ。通过实验可知,最终得到的磷化膜膜层晶粒尺寸较细化,覆盖均匀致密,并具有较好耐蚀性能及优异导电性能。In order to improve the performance and safety of magnesium alloy products,as well as the application in military,electrical appliances and communication equipment,it is of great significance to study magnesium alloy corrosion resistant and conductive chemical conversion coatings.Corrosion resistant and conductive phosphating films were prepared by zinc-based phosphating solution on the surface of AZ91 D magnesium alloy to study the effects of different additives and NaNO3 with different mass concentrations on the properties of magnesium alloy phosphating films.SEM and EDS were used to characterize the film surface morphology and element composition,electrochemical workstation and potassium permanganate drop solution were used to test the film icorr and drop time to judge the corrosion resistance,and digital multimeter was used to test the film surface contact resistance to judge the conductivity.The results show that when 1 g/L calcium nitrate is added,the icorr of the phosphating film is reduced from 44.5μA/cm2 to 19.7μA/cm2.After 60 g/L NaNO3 is added,the phosphating film is uniform and dense and the film on theβphase of magnesium alloy is thinner,the drip time of potassium permanganate is 16.5 s and the surface contact resistance can reach 200 mΩ.The experiments show that the finally obtained phosphating film has finer grain size,uniform and complete coverage,and has better corrosion resistance and excellent electrical conductivity.

关 键 词：AZ91D镁合金 锌系磷化 添加剂 耐蚀性能 导电性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]