High Heat Flux Thermal Cycling of Multi-Layered Deposits Using a HVOF Gun: Modelisation and Experiments

The aim of this work was to determine the behavior of multi-layered structures under high heat fluxes. A direct simulation by the implicit finite difference method was used to predict the transient temperature distribution in each layer of the multimaterial. The influence of the thickness of layers was also studied. Experimentally, high heat fluxes were produced using a HVOF gun operated with a methane-oxygen mixture and internally cooled samples. Multi-layered deposits were vacuum plasma sprayed onto a copper block containing coolant channels for a circulation of water. Transient and static tests were performed with heat fluxes up to 100 MW/m² and durations of a few minutes to several hours.