丝网印刷法制备Y改性CuMn2O4尖晶石涂层研究

Y Modified CuMn2O4 Spinel Coatings Prepared by Screen Printing

目的提高SOFC金属连接件CuMn2O4尖晶石涂层高温抗氧化性能和导电性能。方法采用溶胶-凝胶法制备Y改性CuMn2O4尖晶石粉末,采用丝网印刷技术在SUS430合金表面制备Y改性CuMn2O4尖晶石涂层。利用XRD、SEM表征Y改性CuMn2O4尖晶石粉体及涂层的物相结构及微观形貌。利用氧化增重实验研究Y改性前后CuMn2O4尖晶石涂层试样在800℃空气中氧化168 h的高温氧化行为,通过“四点法”测量涂层在高温氧化过程中的面比电阻值。结果CuMn2O4尖晶石粉末的晶格常数随着稀土Y含量的增大而增大,当Y元素的含量为0.02 mol/L时,晶格常数增幅趋于平缓,此时所得粉体物相结构稳定,结晶程度较好,晶粒尺寸细小且颗粒间团聚现象较少。Y改性前后CuMn2O4尖晶石涂层试样的氧化动力学曲线均遵循抛物线氧化定律,其氧化速率常数分别为9.39×10^−5、6.31×10^−5 mg^2/(cm^4·h)。Y改性CuMn2O4尖晶石涂层试样在800℃氧化168 h时的面比电阻值约为26.2 mΩ·cm^2,低于未改性涂层试样的面比电阻值(约27.3 mΩ·cm^2)。结论Y改性CuMn2O4尖晶石涂层能有效改善金属连接体的高温抗氧化性能和导电性能。

The work aims to improve the high temperature oxidation resistance and electrical conductivity of CuMn2O4 spinel coatings.Y modified CuMn2O4 spinel powder was prepared by sol-gel method.Y modified CuMn2O4 spinel coating was prepared on the surface of SUS430 alloy by screen printing.The phase structure and microstructure of Y modified CuMn2O4 spinel powder and coating were characterized by XRD and SEM.The high temperature oxidation behavior of CuMn2O4 spinel coating before and after Y modification in air at 800℃for 168 h was studied by weight gain experiment.The area specific resistance of coating was measured by the“four-point method”.It was found that the lattice constant of CuMn2O4 spinel powder increased with the increasing of the content of rare earth Y.When the content of Y element was fixed at 0.02 mol/L,the increasing trend of lattice constant tended to be smooth and the modified CuMn2O4 spinel powder with stable structure,high crystallinity,fine grain size and less agglomeration could be obtained.The oxidation kinetics curves of CuMn2O4 spinel coating before and after Y modification followed the parabolic oxidation law,and the oxidation rate constants were 9.39×10^−5 mg^2/(cm^4·h)and 6.31×10^−5 mg^2/(cm^4·h),respectively.The area specific resistance of the Y modified CuMn2O4 spinel coating oxidized at 800℃for 168 h was about 26.2 mΩ·cm^2,which was lower than that of unmodified coating(about 27.3 mΩ·cm^2).The Y modified CuMn2O4 spinel coating can effectively improve the high temperature oxidation resistance and electrical conductivity of metal interconnects.