铜钴镍离子对镁合金微弧氧化膜的影响  

Effects of Copper, Cobalt and Nickel Ions on Micro-arc Oxidation Film of Magnesium Alloy

作　　者：邵忠财[1] 戴诗行 张瑜 赵佳新 代永祺 魏守强[1] SHAO Zhong-cai;DAI Shi-hang;ZHANG Yu;ZHAO Jia-xin;DAI Yong-qi;WEI Shou-qiang(School of Environmental and Chemical Engineering, 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：《表面技术》2018年第4期127-132,共6页Surface Technology

基　　金：辽宁省"大学生创新创业训练计划"项目(201610144011);辽宁省自然科学基金(201602648)~~

摘　　要：目的提高镁合金微弧氧化膜的耐蚀性。方法在Na_2SiO_3-NaOH-Na_2B_4O_7组成的电解液体系中,分别加入铜离子、钴离子和镍离子对AZ91D镁合金进行微弧氧化,研究离子种类和组成对膜层性能的影响。采用点滴实验测试膜层的耐蚀性,采用电化学工作站测试膜层的电化学性能,采用扫描电子显微镜(SEM)和能谱分析(EDS)对微弧氧化膜层的表面形貌和元素组成进行分析。结果电解溶液中加入钴离子、铜离子、镍离子后,镁合金微弧氧化膜的耐腐蚀性能均有提高。其中铜离子的影响最大,加入1.5 g/L的铜离子后,镁合金微弧氧化膜的点滴时间提高了77.3 s,膜层耐腐蚀性能显著提高。电化学测试结果得出,不加金属离子的氧化膜的腐蚀电流密度为1.092×10^(-5) A/cm^2,腐蚀电位为-1.487 V;加入钴、铜、镍离子浓度分别为2、1.5、3 mol/L时,腐蚀电流密度分别为3.912×10^(-6)、6.027×10^(-6)、2.167×10^(-6) A/cm^2,腐蚀电位分别为-1.412、-0.832、-1.047 V;加入金属离子制得的微弧氧化膜的腐蚀电流密度均降低了1个数量级,腐蚀电位不同程度地正移,其中加入铜离子后腐蚀电位提高了0.655 V。加入金属离子后,陶瓷膜表面空隙和孔洞数量不同程度地变浅和减少,增加了膜层的致密性和均匀性。结论电解液中添加一定量的铜、钴、镍离子均能够提高AZ91D镁合金微弧氧化膜层的耐蚀性,其中铜离子的效果最明显。The work aims to improve the corrosion resistance of magnesium alloy micro arc oxidation film. Copper, cobalt and nickel ions were respectively added to the electrolyte system composed of Na2SiO3-NaOH-Na2B407 for micro arc oxidation of AZ91D magnesium alloy. The effect of ion species and composition on the film properties was studied. The corrosion resis- tance of film was measured by drop test; the electrochemical performance of film was measured by electrochemical workstation; the surface morphology and elements of generated micro-arc oxidation film were analyzed by scanning electron microscopy （SEM） and energy spectrum diagram （EDS）. When cobalt ion, copper ion and nickel ion were added into the electrolytic solution, the corrosion resistance of the micro arc oxidation film on the magnesium alloy was improved and the copper ion played the most important role. With addition of 1.5 g/L copper ions, the drop time of micro arc oxidation film on magnesium alloy was improved by 77.3 s, and the corrosion resistance of the film increased significantly. From polarization curve analysis, the corro- sion current of oxide film without metal ions was 1.092×10^-5 A/cm^2 and the corrosion potential was 1.487 V. When concentra- tion of cobalt, copper and nickel ions was respectively 2 mol/L, 1.5 mol/L and 3 mol/L, the corrosion current was respectively 3.912×10^-6 A/cm^2, 6.027×10^-6 A/cm^2 and 2.167×10^-6 A/cm^2 and thecorrosion potential was respectively 1.412 V, 0.832 V and 1.047 V. The corrosion current of the micro arc oxidation film prepared by adding metal ions reduced by 1 orders of magnitude, and the positive shift of the potential was in different degrees. Added with copper ions, the corrosion potential increased by 0.655 V. With the addition of metal ions, the number of voids and holes on the surface of the micro arc oxidation film reduced and decreased in a certain degree, which increasedthe density and uniformity of the film. The addition of a certain amount of copper, cobalt and nickel ions in the el

关 键 词：镁合金 微弧氧化 耐蚀性 铜离子 钴离子 镍离子 

分 类 号：TG174.45[金属学及工艺—金属表面处理]