Thermal shock resistance of ZrO2-CeO2/Al2O3 composite ceramic coating on superalloy GH3039 by sol-gel method

Affiliation of Author(s):材料科学与技术学院

Journal:Fuhe Cailiao Xuebao

Abstract:Preparation of Al2O3 sol and ZrO2 and CeO2 ceramic powder based on sol-gel method were prepared. The ceramic powders were dispersed in Al2O3 sol to form the composite slurry, then ZrO2/Al2O3 and ZrO2-CeO2/Al2O3 composite ceramic coatings were prepared on the surface of superalloy GH3039 substrate by XRD, SEM, EDS and DSC to study the influence of different ceramic powder on thermal shock resistance of composite sol-gel coating at 900℃. The results indicate that the pure Al2O3 coating without any ceramic powder has a large number of macro crack, bad surface integrity and easy peeling during the process of sintering; when the ZrO2 ceramic powder is added into the Al2O3 sol, the structure of the ZrO2/Al2O3 composite ceramic coating has no obvious macro crack and the adhesion between the coating and the substrate increases significantly; when CeO2: ZrO2=1: 10 (molar ratio), CeO2 can stabilize the phase transition under high temperature, which can prevent the transition from t-ZrO2 to m-ZrO2. The ceramic particles are dispersed homogeneously in the Al2O3 network film and present the structure of coated ZrO2-CeO2 particles covered with nano Al2O3 particles. This structure makes the thermal shock resistance and spalling resistance of Al2O3 composite ceramic coating more excellent than the ZrO2/Al2O3 composite ceramic coating. ZrO2-CeO2/Al2O3 composite ceramic coatings can solve the thermal coefficient mismatch problem between matrix and Al2O3 coating so as to further improve the performance of matrix thermal shock and prolongs lifetime of the superalloy GH3039. © 2018, Editorial Office of Acta Materiae Compositae Sinica. All right reserved.

ISSN No.:1000-3851

Translation or Not:no

Date of Publication:2018-11-01

Co-author:Yin, Chunsheng,Fang, Chao,Du, Wenbo

Correspondence Author:Yao Zhengjun

Date of Publication:2018-11-01