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EP-4739643-A1 - METHOD FOR MANUFACTURING A PART MADE OF COMPOSITE MATERIAL

EP4739643A1EP 4739643 A1EP4739643 A1EP 4739643A1EP-4739643-A1

Abstract

The invention relates to a method for manufacturing a part (PA) made of a ceramic matrix composite material, the method comprising: - obtaining a fibre preform of the part to be obtained, the preform comprising ceramic or carbon yarns (3) coated with an interphase comprising at least one layer (71) made of boron nitride; - heat treating the at least one layer of boron nitride, after obtaining the preform, by applying a treatment temperature of between 1050°C and 1250°C for a treatment period of between 0.25 hours and 5 hours; and - densifying the preform, after the heat treatment, with the ceramic matrix (5). Drawing_references_to_be_translated

Inventors

  • COSSOU, Benjamin
  • DELCAMP, ADRIEN
  • Denneulin, Sébastien

Assignees

  • Safran Ceramics

Dates

Publication Date
20260513
Application Date
20240628

Claims (8)

  1. [Claim 1] Method for manufacturing a part (PA; PC) made of ceramic matrix composite material, comprising: - obtaining (E10; Eli) a fibrous preform of the part to be obtained comprising ceramic or carbon wires (3) coated with an interphase comprising at least one layer (71) of boron nitride formed by chemical vapor infiltration, - a heat treatment (E20) of said at least one layer of boron nitride, after obtaining the preform, by applying a treatment temperature of between 1175°C and 1225°C for a treatment duration of between 0.25 hours and 5 hours, and - densification (E30) of the preform, after heat treatment, by the ceramic matrix (5).
  2. [Claim 2] Method for manufacturing a part (PA; PC) in ceramic matrix composite material, comprising: - obtaining (E12) ceramic or carbon wires (3) coated with an interphase comprising at least one layer (71) of boron nitride, the coating of the wires with the interphase being carried out by chemical vapor deposition, - a heat treatment (E200) of said at least one layer of boron nitride on the wires by applying a treatment temperature of between 1175°C and 1225°C for a treatment duration of between 0.25 hours and 5 hours, - the production of a fibrous preform (E14) of the part to be obtained from the threads thus coated, after the heat treatment, comprising the formation of a fibrous blank by implementing one or more textile operations, and the shaping of this blank, and - the densification (E300) of the preform thus produced by the ceramic matrix (5).
  3. [Claim 3] A method according to claim 1 or 2, wherein the treatment time is between 1 hour and 2 hours.
  4. [Claim 4] A method according to any one of claims 1 to 3, wherein the interphase comprises a first (7) and a second (71) boron nitride layer, the second layer covering the first layer, and wherein: - heat treatment (E20; E200) is carried out after the formation of the first and second layers, and - a preliminary stabilization heat treatment is carried out after the formation of the first layer and before the formation of the second layer by imposing a temperature greater than 1300°C and at least equal to the maximum temperature encountered subsequently until completion of the densification of the preform by the matrix (5) for a duration of between 0.25 hours and 5 hours.
  5. [Claim 5] Method according to any one of claims 1 to 4, in which the densification (E30; E300) comprises at least the formation, by chemical vapor infiltration, of a matrix phase (5) of silicon carbide covering said at least one layer (71) of boron nitride.
  6. [Claim 6] The method of claim 5, wherein the densification (E30; E300) further comprises: - the introduction of silicon carbide particles, possibly with added carbon particles, into the residual porosity of the preform densified by the silicon carbide matrix phase, and - the formation of a second Si-SiC matrix phase covering the silicon carbide matrix phase by infiltration of silicon or a silicon alloy after introduction of the particles.
  7. [Claim 7] A method according to any one of claims 1 to 6, wherein the fibrous preform has a three-dimensional weave.
  8. [Claim 8] A method according to any one of claims 1 to 7, wherein the wires (3) are made of silicon carbide and at least part of the matrix (5) is made of silicon carbide.

Description

Description Title of the invention: Method for manufacturing a part made of composite material Technical Domain [0001] The present disclosure relates to a method of manufacturing a part made of a ceramic matrix composite material ("Ceramic Matrix Composite"; "CMC"), for example with a silicon carbide matrix, having improved damage tolerance. Previous technique [0002] Ceramic matrix composite materials withstand temperatures ranging from 600°C to 1400°C. Due to their better resistance to high temperatures, CMCs require less cooling. Since this cooling traditionally comes from a tapping in the compressor which impacts the efficiency of the turbomachine, CMC materials therefore make it possible to improve engine efficiency which reduces fuel consumption. Furthermore, their use contributes to optimizing the performance of turbomachines, in particular by reducing the overall mass of the turbomachine which further contributes to a reduction in fuel consumption and therefore to a significant reduction in pollutant emissions. [0003] CMC parts can be manufactured by forming a silicon carbide pre-densification matrix in the porosity of a fibrous preform, followed by the introduction of silicon carbide particles and siliciding. This method makes it possible to obtain a fully dense Si-SiC matrix of high modulus and a composite with a high linearity limit. In the range mentioned, the wires are initially covered with an amorphous boron nitride (BN) interphase which acts as a mechanical fuse, mainly by means of a fiber/BN debonding allowing the consumption of cracking energy and the deflection of the matrix cracks to prevent them from reaching the fiber reinforcement. FR 2 995 892 is particularly known, which discloses the performance of a heat treatment of i stabilization of the boron nitride of the interphase at a temperature above 1300°C and at least equal to the maximum temperature encountered thereafter until densification is complete. This treatment freezes the structure of the boron nitride and limits its reactivity with ambient air. This treatment is also likely to strengthen the bond with the fiber and densify the coating. [0004] However, the fracture behavior (elongation at break) of parts obtained by known techniques can be variable, thus reducing the damage tolerance zone of the material. Disclosure of the invention [0005] The present invention relates, according to a first embodiment, to a method of manufacturing a part made of ceramic matrix composite material, comprising: - obtaining a fibrous preform of the part to be obtained comprising ceramic or carbon wires coated with an interphase comprising at least one layer of boron nitride, - a heat treatment of said at least one layer of boron nitride, after obtaining the preform, by applying a treatment temperature of between 1050°C and 1250°C for a treatment duration of between 0.25 hours and 5 hours, and - densification of the preform, after heat treatment, by the ceramic matrix. [0006]This case corresponds to a heat treatment carried out on the already formed fiber preform and whose wires are coated with the boron nitride interphase. [0007] The present invention relates, according to a second embodiment, to a method of manufacturing a part made of ceramic matrix composite material, comprising: - obtaining ceramic or carbon wires coated with an interphase comprising at least one layer of boron nitride, - a heat treatment of said at least one layer of boron nitride on the wires by applying a treatment temperature of between 1050°C and 1250°C for a treatment duration of between 0.25 hours and 5 hours, - the production of a fibrous preform of the part to be obtained from the threads thus coated, after heat treatment, comprising the formation of a fibrous blank by implementing one or more textile operations, and the shaping of this blank, and - the densification of the preform thus produced by the ceramic matrix. [0008]This case corresponds to a heat treatment carried out at the wire stage, before formation of the fiber preform. [0009] The inventors found that the variability of mechanical behavior observed was linked to the operation of the interphase between the fibers and the matrix. In the first and second embodiments described above, the heat treatment implemented makes it possible to promote intra-BN cracking and no longer at the fiber/BN interface as usual. The invention is remarkable for the use of this heat treatment which makes it possible to reduce the fiber/matrix interfacial bond strength and makes it possible to increase the potential for crack deflection before they reach the fiber reinforcement, which makes it possible to reduce the variability of the observed fracture behavior. This heat treatment, carried out under controlled duration and temperature conditions, makes it possible to finely control the strength of the fiber/matrix bond while maintaining a sufficiently strong bond which contributes to obtaining the desired mechanical properties