Abstract
The microstructure of thermal barrier coatings (TBC) plays an important role in the thermal cycling behavior of TBCs. In this study, ceramic coatings with different pore structures were prepared by atmospheric plasma spraying (APS). Graphite with different morphology was used as pore former to adjust the pore structure of the coatings. Then, the thermal cycling behavior of TBCs with different structure was characterized. By depositing a porous 8YSZ layer on the conventional 8YSZ layer, the thermal cycling life of TBCs can be improved. However, when the porosity of the porous layer increased to about 30%, the porous layer detached from the under layer after several cycles. An elastic energy model was applied to explain the thermal cycling behavior of TBCs
