Abstract: A core for producing a blade is formed by molding a fibrous preform around the core. The core extends in a longitudinal direction (L) between a root and a tip and has a first face and a second face connected to each other at a first longitudinal edge and at a second longitudinal edge. The core includes fluid passages formed in a transverse thickness of the core, these fluid passages being adapted to allow the passage of fluid from the first face to the second face and vice versa.

Abstract: A method including a step of forming a bond coating on a surface of a substrate, and a step of forming a barrier coating on the bond coating. The bond coating is formed by chemical vapor deposition, at a deposition temperature higher than 150° C., in particular 1200° C. or higher, of a precursor including silicon, and includes columnar grains of crystalline silicon.

Abstract: A part made of coated composite material, includes a substrate made of ceramic matrix composite material; a tie-coat layer covering the substrate; and a protective coating on the tie-coat layer and defining an environmental barrier, the protective coating including a rare-earth silicate and including a first outer region including an outer surface of the protective coating opposite to the substrate and having a first working creep, having deformation of less than or equal to 0.07% when a compressive stress of at least 50 MPa is applied for a duration of 10 hours at a temperature of between 1050° C. and 1300° C. The first region includes a grain growth inhibitor; and a second, inner, environmental barrier region, including an interface of the protective coating with the tie-coat layer and having a second working creep.

Abstract: A part includes a substrate of ceramic matrix composite material, the substrate including silicon, the part further including an environmental barrier formed on at least one surface of the substrate, wherein the environmental barrier includes at least one compound selected from Yb2-2?Gd2?SiO5 and Yb2-2?Gd2?Si2O7, where ? is between 0.05 and 0.15, and wherein the environmental barrier further includes alumina Al2O3, the molar alumina content being between 5% and 15% of the total environmental barrier composition.

Abstract: A method for coating a ceramic matrix composite part with an environmental barrier, includes a) applying, to the surface of the part, a coating composition including a first powder of a rare earth silicate and a second powder including boron, the coating composition having a ratio R=[mass of the second powder]/[mass of the first powder] of between 0.1% and 5%, wherein the second powder includes a boron powder, and b) sintering the first and second powders in order to obtain the environmental barrier on the part.

Abstract: A method for coating a ceramic matrix composite part with an environmental barrier, the method including a) applying, to a surface of the part, a coating composition including a first powder of a rare earth silicate and a second powder including boron, the coating composition having a ratio R=[mass of the second powder]/[mass of the first powder] of between 0.1% and 5%, and b) sintering the first and second powders to obtain the environmental barrier on the part.

Abstract: A part includes a substrate, having, adjacent to a surface of the substrate, at least a portion that is made from a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including at least a first layer including a rare earth disilicate of formula REa2Si2O7 present at a molar content lying in the range 70% to 99.9%, where REa is a rare earth element; and at least one rare earth oxide of formula REb2O3 present at a molar content lying in the range 0.1% to 30%, where REb is a rare earth element different from REa.

Abstract: A method for coating a ceramic matrix composite part with an environmental barrier, the method including a) applying, to a surface of the part, a coating composition including a first powder of a rare earth silicate and a second powder including boron, the coating composition having a ratio R=[mass of the second powder]/[mass of the first powder] of between 0.1% and 5%, and b) sintering the first and second powders to obtain the environmental barrier on the part.

Abstract: A part includes a substrate having, adjacent to a surface of the substrate, at least a portion that is made of a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including a first layer including at least one first rare earth silicate and presenting grains with a mean size less than or equal to 1 ?m; and a second layer covering the first layer, the second layer including at least one rare earth silicate and presenting grains with a mean size greater than 1 ?m.

Abstract: A part includes a substrate having, adjacent to a surface of the substrate, at least a portion that is made of a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including a first layer including at least one first rare earth silicate and presenting grains with a mean size less than or equal to 1 ?m; and a second layer covering the first layer, the second layer including at least one rare earth silicate and presenting grains with a mean size greater than 1 ?m.

Abstract: A part includes a substrate, having, adjacent to a surface of the substrate, at least a portion that is made from a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including at least a first layer including a rare earth disilicate of formula REa2Si2O7 present at a molar content lying in the range 70% to 99.9%, where REa is a rare earth element; and at least one rare earth oxide of formula REb2O3 present at a molar content lying in the range 0.1% to 30%, where REb is a rare earth element different from REa.