MULTILAYERED THERMAL AND ENVIRONMENTAL BARRIER COATING (EBC) FOR HIGH TEMPERATURE APPLICATIONS AND METHOD THEREOF

摘要

An air plasma method for the deposition of an advanced EBC coating system, and an EBC coating system.

主权项

1. An air plasma method for the deposition of an advanced EBC coating system, comprising
applying a silicone bond coat to a SiC substrate; exposing the silicone bond coat to oxygen to form a proactive SiO2 thermally grown oxide (TGO) layer to avoid decomposition of the SiC substrate to SiO2 and gaseous CO; applying a layer of mullite over the silicon bond coat to impede diffusion of oxygen to the silicon bond coat; and applying a ytterbium disilicate topcoat over the layer of mullite, the ytterbium disilicate having a very low silica volatility and protecting the layer of mullite and silicon layer from volatilization by water vapor.