The nature and magnitude of residual stresses in thermal-sprayed coatings determine their lifetime and failure mechanisms. The residual stresses of suspension high-velocity oxy-fuel (SHVOF) thermal sprayed alumina (Al2O3) coating were measured with hole-drilling and x-ray diffraction. The coating is dense and consists of amorphous and two crystalline phases: alpha and gamma. The residual stresses measured by hole-drilling in the Al2O3 coating was − 162 MPa (compression) in the longitudinal direction and − 104 MPa (compression) in the transverse direction. This is due to the peening stress and the high substrate–coating CTE ratio of ~ 2.1. The nature of the residual stress through the coating is related to the microstructure build-up shown from the cross section and the fracture surfaces of the coating.

中文翻译：

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通过钻孔法测量悬浮 HVOF 喷涂氧化铝涂层的残余应力

热喷涂涂层中残余应力的性质和大小决定了它们的寿命和失效机制。用钻孔和 X 射线衍射测量悬浮高速氧燃料 (SHVOF) 热喷涂氧化铝 (Al2O3) 涂层的残余应力。涂层致密，由非晶相和两个结晶相组成：α 和 γ。通过在 Al2O3 涂层中钻孔测量的残余应力在纵向为 - 162 MPa（压缩），在横向为 - 104 MPa（压缩）。这是由于喷丸应力和约 2.1 的高基材-涂层 CTE 比。通过涂层的残余应力的性质与从涂层的横截面和断裂表面显示的微观结构积聚有关。