氨三乙酸对镁合金复合阳极氧化膜的影响  

Effects of Nitrilotriacetic Acid on Properties of Composite Anodizing Films on Mg Alloy

作　　者：王敬[1,2] 王勇[3] 郭星星[2] 

机构地区：[1]重庆广播电视大学汽车工程学院,重庆400074 [2]重庆大学材料科学与工程学院,重庆400044 [3]重庆电子工程职业学院汽车工程系,重庆401331

出　　处：《热加工工艺》2015年第4期197-200,共4页Hot Working Technology

摘　　要：采用阳极氧化的方法在AZ31镁合金表面制备包含Al2O3纳米颗粒的复合阳极氧化膜,研究了氨三乙酸(NTA)对复合阳极氧化膜的影响。分别利用涡流测厚仪、扫描电镜、电化学工作站依次对复合氧化膜进行厚度测量、形貌观察和极化曲线分析。结果显示,氨三乙酸参与了阳极氧化过程,并改变击穿电压,适量氨三乙酸能有效降低氧化膜的孔隙率和增加氧化膜厚度。且氨三乙酸的添加量在0.04 mol/L时,复合阳极氧化膜耐蚀性相对最优,氧化膜的自腐蚀电位高达-0.84 V,自腐蚀电流密度降低了3个数量级。Composite anodizing coatings containing superfine Al2O3 were prepared on AZ31 Mg alloy surface by anodic oxidation method. The effects of nitrilotriacetic acid（NTA） on properties of composite anodizing films were studied by eddy current thickness tester, SEM and electrochemical workstation, the thickness of composite anodizing coatings, micro morphology and polarization curves were discussed, respectively. The results show that NTA can participate in the coating formation and increase the breakdown voltage. Appropriate amount of nitrilotriacetic acid can effectively reduce the porosity of films and increase the thickness of films. The corrosion potential of composite anodizing films with 0.04 mol/L NTA is up to-0.84 V, the corrosion current density decreases by 3 orders of magnitude, which shows better corrosion resistance.

关 键 词：氨三乙酸 阳极氧化 镁合金 极化曲线 

分 类 号：TG146.2[一般工业技术—材料科学与工程]