Effects of surface roughness on CMAS corrosion behavior for thermal barrier coating applications

Journal of Advanced Ceramics

Zhilin Gan¹  Guang Li¹  Lei Guo² 

[1] School of Materials Science and Engineering, Tianjin University, 300072, Tianjin, China;School of Materials Science and Engineering, Tianjin University, 300072, Tianjin, China;Tianjin Key Laboratory of Advanced Joining Technology, Key Lab of Advanced Ceramics and Machining Technology of Ministry of Education, 300072, Tianjin, China;

关键词: thermal barrier coating (TBC);    calcium-magnesium-alumina-silicate (CMAS);    surface roughness;    wetting;    spreading;   

DOI  :  10.1007/s40145-020-0449-7

来源: Springer

【 摘 要 】

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.

【 授权许可】

CC BY