Abstract: The present invention relates to a method for manufacturing a part, comprising the steps of chemically etching, in a wet acid medium, at least a portion of a surface of a substrate made of a monocrystalline superalloy, comprising at least one element chosen from rhenium and ruthenium, the substrate having a ?-?? phase, the substrate having an average mass fraction of rhenium and/or ruthenium greater than or equal to 3%, the chemical etching being done in such a way that the average mass fraction of rhenium and/or ruthenium over the portion of the surface of the substance is less than 2%, and a step of depositing on the portion of the substrate a protective coating having a ?-?? phase and an average mass fraction of rhenium and/or ruthenium of less than 1%.

Abstract: The present invention concerns a turbine part comprising a substrate made of nickel-based monocrystalline superalloy, comprising chromium and at least one element chosen among rhenium and ruthenium, the substrate having a ?-?? phase, an average mass fraction of rhenium and of ruthenium greater than or equal to 4% and an average mass fraction of chromium less than or equal to 5% and preferably less than or equal to 3%, a sub-layer covering at least a part of a surface of the substrate, characterised in that the sublayer has a ?-?? phase and an average atomic fraction of chromium greater than 5%, of aluminium between 10% and 20% and of platinum between 15% and 25%.

Abstract: A nickel-based superalloy part includes a nickel-based superalloy substrate, and a metal sublayer covering the substrate, wherein the metal sublayer includes a first and a second layer, the first layer being located between the substrate and the second layer, the first layer including a first ??-Ni3Al phase and a second ?-Ni phase, the second layer including a first ??-Ni3Al phase, a second ?-Ni phase and a third ?-NiAl phase, the average atomic fraction of aluminum in the second layer being strictly greater than the average atomic fraction of aluminum in the first layer.

Abstract: A protection method protects at least one hollow internal area of a turbine engine part made of a superalloy from oxidation and/or corrosion, wherein the at least one hollow inner area has been formed by means of at least one core made of a ceramic material limited by an external surface that surrounds it. Before bringing the superalloy around the core made of a ceramic material, the external surface is coated with a material that includes a nanometric layer of hafnium (Hf), and/or a micrometric layer of platinum (Pt), or a mixture at least of hafnium and platinum.

Abstract: A process for coating a refractory alloy part is provided and includes coating an area of a refractory alloy part by means of a treatment composition including a type of preceramic polymer and a solvent, and heat treating the part coated with the treatment composition. The heat treating partially converts the preceramic polymer and forms a ceramic coating obtained by conversion, the ceramic coating protecting the refractory alloy from oxidation. The treatment composition also includes active fillers to form an alloy coating on a surface of the part by solid diffusion in addition to the ceramic coating obtained by conversion, and the alloy coating generates a protective oxide layer when subjected to oxidizing conditions.

Abstract: A process for coating a part by chemical vapor diffusion is provided and includes placing a powder mixture in a chamber, immersing the part partially in the powder mixture, and applying a heat treatment to the part. The powder mixture includes a first component and a second component forming a gaseous compound during the heat treatment so as to allow deposition of the second component on the part. The part includes a metal refractory allow and the second component forms a solid diffusion alloy by solid diffusion with a metal species of the refractory metal alloy to generate a coating. The solid diffusion allow generates a passivating oxide layer when subjected to oxidizing conditions.

Abstract: A part includes a substrate made of a nickel-based superalloy, the substrate having a first average mass fraction of one or more first elements chosen from hafnium, silicon and chromium, the substrate having an open cavity in the part and a cooling channel, the substrate further including a surface layer partially forming the cavity, the surface layer having a second average mass fraction of the first element or first elements which is greater than the first average mass fraction.

Abstract: A process for protecting a part made of a hafnium-free nickel-based single-crystal superalloy against corrosion and oxidation includes manufacturing a part made of a hafnium-free nickel-based single-crystal superalloy, depositing successively on the part, a first layer including hafnium, then a mixed layer of stacked layers of an undercoat of an alloy having 10 atomic % or more of aluminum and a second layer including hafnium or a mixed layer of an alloy of aluminum and hafnium, and then a third layer including hafnium, and diffusing and performing an oxidation treatment so as to obtain a hafnium-doped alumina layer.

Abstract: A component includes a substrate at least a portion of which adjacent to a surface of the substrate is made of a material including silicon; a bond coat located on the surface of the substrate and including silicon, an environmental barrier which includes an outer layer of ceramic material covering the bond coat, wherein the environmental barrier further includes a self-healing inner layer located between the bond coat and the outer layer, the inner layer including a matrix in which silico-forming particles are dispersed, these particles being capable of generating a matrix crack healing phase in the presence of oxygen.

Abstract: The present invention relates to a method for the protection of a hafnium-free, nickel-based monocrystalline superalloy part against corrosion and oxidation. The method comprises at least the following steps of: manufacturing a hafnium-free, nickel-based monocrystalline superalloy part (1), depositing on the part a first hafnium-free sublayer (2), depositing, on the first sublayer (2), a second hafnium-doped sublayer (3), depositing, on the second sublayer (3), a third hafnium-free sublayer (4), sandblasting the third sublayer (4) to at least partially separate the third sublayer (4) and increase the surface roughness of an upper sub-layer formed by the second sublayer (3) and at least partially by the third sublayer (4), performing oxidation treatment so as to obtain at the surface a layer of hafnium-doped oxidised material (5), depositing a thermal barrier layer (6) on the layer of oxidised material (5).

Abstract: The invention relates to a part made of silicon-based ceramic material or silicon-based ceramic matrix composite (CMC) material comprising an environmental barrier coating (EBC), said coating (12, 13) comprising a bonding layer (12) deposited on the surface of the ceramic material or ceramic matrix composite (CMC), said bonding layer (12) being topped by one or more layers together forming a multifunctional barrier structure (13), characterised in that the bonding layer (12) has at its interface with the multifunctional structure a polycrystalline silica layer (12) or sub-layer (12b).

Abstract: The invention concerns a turbine component, such as a turbine blade or a distributor fin, for example, comprising a substrate made from single-crystal nickel superalloy, and a metal sublayer covering the substrate, characterised in that the metal sublayer comprises at least two elementary layers, including a first elementary layer and a second elementary layer, the first elementary layer being arranged between the substrate and the second elementary layer, each elementary layer comprising a ??-Ni3Al phase, and optionally a ?-Ni phase, and in that the average atomic fraction of aluminum in the second elementary layer is strictly greater than the average atomic fraction of aluminum in the first elementary layer.

Abstract: A turbine component includes a substrate made from monocrystalline nickel-based superalloy including rhenium, which has a ?-?? Ni phase, and an average weight faction of chromium of less than 0.08, a sublayer made from nickel-based metal superalloy covering the substrate, in which the sublayer made from metal superalloy includes at least aluminium, nickel, chromium, silicon, hafnium and has, predominantly by volume, a ??-Ni 3 Al phase.

Abstract: The present invention concerns a turbine part comprising a substrate made of nickel-based monocrystalline superalloy, comprising chromium and at least one element chosen among rhenium and ruthenium, the substrate having a ?-?? phase, an average mass fraction of rhenium and of ruthenium greater than or equal to 4% and an average mass fraction of chromium less than or equal to 5% and preferably less than or equal to 3%, a sub-layer covering at least a part of a surface of the substrate, characterised in that the sublayer has a ?-?? phase and an average atomic fraction of chromium greater than 5%, of aluminium between 10% and 20% and of platinum between 15% and 25%.

Abstract: A turbine part, such as a turbine blade or a distributor fin, for example, including a substrate made of superalloy based on monocrystalline nickel, including rhenium and/or ruthenium, and having a ??-NisAI phase that is predominant by volume and a ?-Ni phase, the part also including a sublayer made of metal superalloy based on nickel covering the substrate, wherein the sublayer has a ??-NisAI phase that is predominant by volume and wherein the sublayer has an average atomic fraction of aluminium of between 0.15 and 0.25, of chromium of between 0.03 and 0.08, of platinum of between 0.01 and 0.05, of hafnium of less than 0.01 and of silicon of less than 0.01. A process for manufacturing a turbine part including a step of vacuum deposition of a sublayer made of a superalloy based on nickel having predominantly by volume a ??-NisAI phase, on a substrate made of superalloy based on nickel including rhenium and/or ruthenium.

Abstract: A process for coating a refractory alloy part is provided and includes coating an area of a refractory alloy part by means of a treatment composition including a type of preceramic polymer and a solvent, and heat treating the part coated with the treatment composition. The heat treating partially converts the preceramic polymer and forms a ceramic coating obtained by conversion, the ceramic coating protecting the refractory alloy from oxidation. The treatment composition also includes active fillers to form an alloy coating on a surface of the part by solid diffusion in addition to the ceramic coating obtained by conversion, and the alloy coating generates a protective oxide layer when subjected to oxidizing conditions.

Abstract: A process for coating a part by chemical vapor diffusion is provided and includes placing a powder mixture in a chamber, immersing the part partially in the powder mixture, and applying a heat treatment to the part. The powder mixture includes a first component and a second component forming a gaseous compound during the heat treatment so as to allow deposition of the second component on the part. The part includes a metal refractory allow and the second component forms a solid diffusion alloy by solid diffusion with a metal species of the refractory metal alloy to generate a coating. The solid diffusion allow generates a passivating oxide layer when subjected to oxidizing conditions.

Abstract: The invention relates to a process for manufacturing a part made of nickel-based monocrystalline superalloy containing hafnium. This process is noteworthy in that it comprises the following successive steps consisting in: —manufacturing a nickel-based monocrystalline superalloy that is not doped with hafnium, —manufacturing a part from this superalloy, —directly depositing on said part a layer of hafnium having a thickness of between 50 nm and 800 nm, —carrying out a diffusion treatment of the hafnium so as to form an interdiffusion layer at the surface of said part and to thus obtain a part made of nickel-based monocrystalline superalloy containing hafnium.

Abstract: A turbine component includes a substrate made from monocrystalline nickel-based superalloy including rhenium, which has a ?-?? Ni phase, and an average weight faction of chromium of less than 0.08, a sublayer made from nickel-based metal superalloy covering the substrate, in which the sublayer made from metal superalloy includes at least aluminium, nickel, chromium, silicon, hafnium and has, predominantly by volume, a ??-Ni 3 Al phase.

Abstract: The invention relates to a method for producing a metal bladed element for a turbomachine of an aircraft, said bladed element comprising at least one blade having a lower surface and an upper surface extending between a leading edge and a trailing edge of the blade, the trailing edge having to have a thickness Xl, said method comprising the steps of: a) producing the bladed element by lost-wax casting, and b) finishing the bladed element, characterised in that step b) comprises the chemical milling at least of the trailing edge of the or each blade so as to obtain said thickness X1 which cannot be directly obtained by step a).