通过丝网印刷法在SS410合金上涂覆YCo0.6Mn0.4O3抗氧化涂层材料,采用氧化增重法、SEM-EDX、四探针法分别对SS410合金及其涂覆抗氧化涂层后的高温氧化速率、微观形貌和面积比电阻进行了表征.结果表明,通过丝网印刷法在合金表面涂覆连续致密的陶瓷涂层材料,YCo0.6Mn0.4O3涂层在循环氧化过程中与基底结合牢固,没有出现剥离脱落.涂覆YCo0.6Mn0.4O3涂层后,在800℃下SS410合金的氧化速率降低1个数量级,在800℃氧化150h合金的面积比电阻由未涂层的72mΩ.cm^2降到了16mΩ.cm^2,大幅度地提高了合金的高温抗氧化性能及电导性能.
High-temperature oxidation-resistant alloys are considered to be one kind of the most promising candidate materials for intermediate temperature solid oxide fuel cells (IT-SOFCs) due to their excellent electrical conductivity, low cost and superior mechanical properties. However, poorly conductive chromium oxide scales forming on the surface of the alloy at high temperature lead to rapid degradation of stack performance. In this work, YCo0.6Mn0.4O3 was initially adopted as the protective coating material for SS410 alloy by screen-printing. The microstructure, mass gain and electrical conductivity of the coated and uncoated samples after oxidation were investigated. The results revealed that an uniform and dense YCo0.6Mn0.4O3 coating formed on the surface of the SS410 and bonded well to the alloy substrate after the thermal cyclic tests owing to well matched thermal expansion between the coating material and the alloy. The parabolic rate constant of the coated alloy was about ten times lower than that of the uncoated alloy after the oxidation test at 800℃. The YCo0.6Mn0.4O3-coated alloy obviously showed a lower area specific resistance of 17 mΩ.cm^2 as compared with that of 72 mΩ.cm^2 for the bare-alloy.