大气等离子喷涂制备SOFC连接体铜掺杂锰钴尖晶石涂层

Atmospheric plasma spraying preparation of SOFC connector copper-doped manganese-cobalt spinel coating

为了进一步提高锰钴尖晶石连接体防护涂层的高温电导率,采用大气等离子喷涂技术制备了铜质量分数占比为5.38%的锰钴尖晶石涂层.通过SEM/EDS,XRD和XPS等方法表征了涂层在不同氧化时间下的微观形貌、物相及元素价态,采用恒定电流为0.2 A的直流四电极法测量涂层的高温电导率.结果表明:氧化四周后的涂层依然保持完整,无开裂及剥落,高温氧化性能良好,在高温条件下保温使涂层与基体中的元素发生了互扩散;750℃下的电导率是20 S/cm,800℃时电导率值稳定在27 S/cm;涂层未检出含Cu尖晶石相,可能是成功掺入尖晶石的Cu元素较少.

In order to further improve the high temperature conductivity of the protective coating of the manganese-cobalt spinel connector,the manganese-cobalt spinel coating with a copper mass fraction of 5.38%was prepared by atmospheric plasma spraying technology.SEM/EDS,XRD and XPS were used to characterize the microscopic morphology,phase and element valence state of the coating at different oxidation times;the high-temperature electrical conductivity of the coating was measured by a DC four-electrode method with a constant current of 0.2 A.The results showed that the coating remained intact after four weeks of oxidation without cracking or peeling.The high-temperature oxidation performance was good.The heat preservation at high temperature caused inter-diffusion of the elements in the coating and the substrate.The conductivity at 750℃was 20 S/cm The conductivity value was stable at 27 S/cm at 800℃.No Cu-containing spinel phase was detected in the coating,which may be due to the fact that less Cu element was successfully doped into the spinel.