Patent ID: 8455103

Claim:
A part comprising: a substrate of ceramic matrix composite material containing silicon; and an environmental barrier formed on the substrate and comprising: an outer anticorrosion protection layer containing a compound comprising an aluminosilicate of an alkali, element, an aluminosilicate of an alkaline-earth element, or an aluminosilicate of a rare-earth element, and a bond sub-layer containing silicon and formed on the substrate, wherein: the bond sub-layer is formed between the substrate and the anticorrosion protection layer, the composition of the bond sub-layer varying from silicon to mullite between an inner face beside the substrate and an outer face, with the silicon content decreasing and the mullite content increasing, the bond sub-layer beginning, beside its inner face, in a layer of silicon formed on the substrate and having a thickness of no more than 50 μm, and the bond sub-layer terminating, beside its outer face, in a layer of mullite having a thickness of no more than 50 μm.