METHOD FOR FORMING AN IMPROVED THERMAL BARRIER COATING (TBC), THERMAL-BARRIER-COATED ARTICLE AND METHOD FOR THE REPAIR THEREOF

摘要

The invention refers to a process for the formation of a thermal barrier coating (102) on a substrate (101), comprising the steps of: a) applying a bond coat (103) on the substrate (101); b) subjecting the bond coat (103) to a low activity aluminizing process, thus obtaining, above the bond coat (103), a temporary intermediate diffusion layer; c) applying, on the temporary intermediate diffusion layer, aluminium powder in suspension with a solvent or aqueous base, said aluminium powder having size distribution from 15 to 150 µm; d) performing a thermal treatment in a vacuum at a pressure from 10-3 to 10-5 bars, at a temperature from 800°C to 1050°C and with an active phase having duration in the range of 60 minutes to 4 hours, thus obtaining above the bond coat (103) an enriched intermediate diffusion layer (105); and e) applying a definitive barrier layer (104) on said enriched intermediate diffusion layer (105).