Calcium-magnesium-alumina-silicate (CMAS) corrosion is an important cause for thermal barrier coating (TBC) failure, which has attracted increased attentions. In this study, some thermal barrier coating (TBC) materials including YSZ (yttria partially stabilized zirconia), GdPO₄, and LaPO₄ were prepared into bulks, and the effects of their surface roughness on wettability and spreading characteristics of molten CMAS were investigated. As-fabricated and polished bulks with different surface roughness were exposed to CMAS corrosion at 1250 °C for 1 and 4 h, following by macro and micro observations. Results revealed that compared with the as-fabricated bulks, molten CMAS on the polished samples had lower wettability and a smaller spreading area, mainly attributable to the reduced capillary force to drive the melt spreading. Meanwhile, GdPO₄ and LaPO₄ bulks exhibited lower CMAS wettability than YSZ bulk. It is thus considered that reducing the surface roughness is beneficial to CMAS corrosion resistance of TBCs.

钙镁铝硅酸盐（CMAS）腐蚀是热障涂层（TBC）失效的重要原因，引起了越来越多的关注。在这项研究中，一些热障涂层（TBC）材料包括YSZ（氧化钇部分稳定的氧化锆），GdPO ₄和LaPO ₄将其制备成块，并研究它们的表面粗糙度对熔融CMAS的润湿性和铺展特性的影响。通过宏观和微观观察，将具有不同表面粗糙度的预制和抛光块在1250°C下暴露于CMAS腐蚀1和4 h。结果表明，与加工后的块体相比，抛光样品上的熔融CMAS具有较低的润湿性和较小的铺展面积，这主要归因于驱动熔体铺展的毛细力减小。同时，GdPO ₄和LaPO ₄块显示出比YSZ块更低的CMAS润湿性。因此认为降低表面粗糙度有利于TBC的CMAS耐腐蚀性。