EB-PVD热障涂层的表观压痕尺寸效应

Apparent Indentation Size Effect of EB-PVD Thermal Barrier Coatings

摘要:

采用Knoop压痕法评价沉积于镍基单晶高温合金基体上的EB—PVD热障涂层的显微硬度。测试结果表明，热障涂层系统的显微硬度存在压痕尺寸效应，即表观显微硬度随施压载荷的增加而显著降低。用弹／塑性模型Knoop压痕能量平衡对表观压痕尺寸效应进行分析，并从实验测试结果分析得出与载荷无关的显微硬度值。

Abstract:

Indentation microhardness testing was used to assess the microhardness of an EB-PVD thermal barrier coatings (TBCs) deposited on a single crystal Ni-base superalloy substrate. Tests performed using a Knoop indenter geometry reveal that there is an indentation size effect (ISE), namely that the apparent microhardness decrease significantly with increasing indentation test load. An energy balance analysis based on elastic/plastic indentation model was applied to analyze the apparent ISE and to extract the load-independent hardness from the experimental measurements.