Abstract
The surfaces of gas turbine components are coated by thermal barrier coatings (TBCs) with a plasma spraying technique. Spallation damage is an essential problem, as well known, in usage of TBC. A lot of efforts for TBC interfacial strength examination had been done, however studies examined how residual stress are formed after the process and also the coating stress changes with temperature were limited. In this report, the residual stress prediction model is proposed based on the splat deposition process. Simplified model including the plasma sprayed process is developed based on shear-lag theory. The simplification is given in continuous particle deposition process. That is, continuous particle deposited coating is modeled as a single layer, which is called by "deposition layer" in this study. This deposition layer is assumed to impact directly onto the substrate. The binding layer is also introduced to express multiple cracks caused by quenching stress in splats and sliding deformation at splat boundary. It is shown that the numerical analysis has good agreement with the associated experiments.
