Chemical Vapour Deposition of TBC: An Alternative Process for Gas Turbine Components

This paper deals with a development of a new process for the deposition of Thermal Barrier Coatings (TBC) based on Chemical Vapour Deposition (CVD). The research program started in September 1998 under a BRITE/Euram III project.The CVD process involves the evaporation of zirconium and yttrium starting from metal-organic precursors and their reaction with oxygen in a hot wall reactor in order to deposit TBC layers.The influence of different deposition parameters such as evaporation temperature, pressure and substrate temperature on structure, deposition rate and process yield are described. The characterisation of different precursors behaviour is also described. Preliminary results, obtained with optimised conditions, have shown ZrO2-Y2O3 columnar layers with deposition rates of interest from an industrial point of view.Copyright © 2000 by ASME