In most high temperature applications, efficiency increases with service temperature of the component. Especially in combustion chambers, higher efficiency is translated into less propellant consumption and therefore a lower weight and a reduction of operational cost. In these components, the use of high performance coatings may simultaneously increase the service temperature and decrease its price. From the many available coating processes, Metal organic Chemical Vapour Deposition (MO-CVD) is one of the few capable of producing coatings of most precious metals in internal surfaces with intricate geometry. Nevertheless the microstructure control of the films is extremely complicated and characterised by the formation of dendrite structures. This morphology eliminates the coating efficiency, as it is not compact. EADS has had the chance to use the research infrastructure of the AMTT in Seibersdorf to characterise the coatings and determine how the transformation from the compact to the non-compact microstructure takes place. The understanding of this phenomenon should allow us to develop a process able to produce 100 % dense coatings independently of the coating thickness in an industrial scale.

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