In this work, the stiffness of an air plasma sprayed thermal barrier coating (APS TBC) was studied using the three-point bending technique. Various measurements over different time periods were made on detached TBC beams, prepared by acid etching, in both as-deposited states and after heat treatment. Monotonic and cyclic loading were conducted to understand the mechanical behaviour of the TBCs in detail. The TBC beams during bending show nonlinear behaviour, inelastic deformation and hysteresis loops. The derived global in-plane elastic modulus, at first increases and then decreases with thermal exposure, and is of the range 14–18 GPa. This behaviour is a result of competition between sintering and development of microstructural damage. Direct microstructural observations during In-situ mechanical testing show that intra-splat opening/closure and inter-splat sliding give rise to the relatively low elastic modulus of the APS TBC.

在这项工作中，使用三点弯曲技术研究了空气等离子喷涂热障涂层（APS TBC）的刚度。在分离的TBC束上进行不同时间段的各种测量，这些束是通过酸蚀刻制备的，既处于沉积状态，也处于热处理之后。进行了单调和循环加载以详细了解TBC的机械性能。弯曲过程中的TBC梁表现出非线性行为，非弹性变形和磁滞回线。导出的全局平面内弹性模量首先随着热暴露而增加，然后减小，范围为14-18 GPa。这种行为是烧结与微观结构破坏发展之间竞争的结果。