Discharge membranes for making composite materials

Abstract

The invention relates to a method for manufacturing a composite part, said method comprising:-arranging a fibrous preform (10) in a mould comprising an impregnation chamber (201) closed by a membrane (230) separating the impregnation chamber (201) from a compaction chamber (202),-injecting an impregnation fluid (5) into the impregnation chamber (201), and injecting a compression fluid (6) into the compaction chamber (202) to apply pressure to the membrane (230), -suction of a compressed fluid (6) present in the compaction chamber (202), said method being characterized in that a surface (230b) of the membrane (230) on the side of the compaction chamber (202) comprises a plurality of grooves (235a, 235b).

Description

Technical Field

[0001] The present invention relates to the production of components made of composite materials, in particular ceramic matrix composites (CMC) or organic matrix composites (OMC). Background Art

[0002] Components made of ceramic matrix composites or organic matrix composites are usually manufactured by impregnating a fiber preform. The fiber preform can be arranged in a mold, closed by a counter-mold. The fiber preform is then impregnated with a slip or resin loaded with precursor matrix particles, depending on the desired matrix type. Impregnation is performed by injecting the slip or resin into the mold cavity including the fiber preform so as to gradually penetrate the fiber preform with the slip or resin.

[0003] However, the infusion schemes using a mold and counter-mold with a defined cavity are not very satisfactory for the manufacture of certain parts, especially for the manufacture of large or low-thickness parts, such as aircraft engine casings or aerospace rear fuselage parts. In addition, these schemes are very limited from the perspective of tool tolerances, which must conform to very precise dimensions.

[0004] In order to overcome these disadvantages, a deformable membrane can be used instead of a counter-mold. For example, such a solution is described in documents US2017334791A1 and US2021046671A1, which describe a method in which a membrane separates an impregnation chamber from a compaction chamber. The preform is arranged in an impregnation chamber. In these methods, an impregnation fluid intended to penetrate into the pores of the preform is injected into the impregnation chamber, and a compressed fluid is injected into the compaction chamber to apply pressure to the membrane, so that the membrane applies pressure to the fiber preform. The injection parameters of the impregnation fluid and the compressed fluid can vary according to the type of part to be produced.

[0005] When the fiber preform is properly impregnated, and after an optional treatment step of the impregnation fluid present in the preform, the compressed fluid present in the compacting chamber is aspirated. However, it has been observed that residual compressed liquid remains in the compacting chamber, even if the discharge operation is repeated several times in succession. Therefore, regular manual cleaning of the tool is required to remove the compressed fluid from the membrane surface and to remove the residual fluid still present in the compacting chamber. This manual cleaning operation is even more problematic because the compressed fluid used may pose a risk to personal health or the environment and may lead to contamination problems in the workshop. Summary of the invention

[0006] The object of the present invention is therefore to overcome the above-mentioned drawbacks by proposing a solution for the manufacture of composite parts limiting the manual handling of the compressed fluid. In particular, it has been observed that during the suction of the compressed fluid for discharge, the membrane may adhere to the walls of the compacting chamber under the effect of the suction, thus preventing the removal of part of the compressed fluid. This mechanism explains the presence of a considerable amount of residual compressed liquid in the compacting chamber even after several consecutive discharge cycles.

[0007] Therefore, the present invention proposes a method for manufacturing a composite material component, comprising the following steps:

[0008] - arranging the fiber preform in a mold comprising an impregnation chamber, the first face of the preform being located on a supporting surface of the impregnation chamber,

[0009] The impregnation chamber is closed by a flexible membrane located on the second face of the preform, said membrane separating the impregnation chamber from the compacting chamber,

[0010] - injecting the impregnation fluid into the impregnation chamber,

[0011] - injecting compressed fluid into the compaction chamber to exert pressure on the membrane,

[0012] - sucking the compressed fluid in the compacting chamber through one or more outlet openings of the compacting chamber,

[0013] The method is characterized in that the surface of the membrane located on the compacting chamber side comprises a plurality of grooves.

[0014] It has been observed that the presence of such grooves on the surface of the membrane makes it possible to reduce the amount of residual compressed fluid present in the compaction chamber after discharge (in other words after suction of the compressed fluid).

[0015] This improvement is explained by the presence of grooves on the surface of the membrane on the compacting chamber side, which grooves allow the compressed fluid to circulate between the membrane and one or more walls of the compacting chamber when the membrane is pressed against the walls of the compacting chamber during the suction step.

[0016] In particular, it can be provided that, when the membrane is pressed against at least one wall of the compacting chamber, a portion of the recess opens into one or more outlet orifices. Thus, during the suction step, the removal of the compressed fluid is greatly facilitated, even if the membrane is pressed against said one or more walls of the compacting chamber. Furthermore, this solution makes it possible to maintain a tool of reduced dimensions without having to enlarge the compacting chamber in order to avoid contact with the membrane. By maintaining a compacting chamber of reduced dimensions, the implementation of the method can be facilitated without having to increase the amount of compressed fluid required for the correct functioning of the tool.

[0017] The impregnating fluid includes one or more matrix precursors.

[0018] According to a particular embodiment of the invention, the groove is arranged so that when the membrane is in contact with the wall of the compacting chamber (usually during the suction step), at least a portion of the groove opens into at least one outlet hole of the compacting chamber or into a space of the compacting chamber comprising at least one outlet hole.

[0019] Thus, when the membrane is sucked against the wall of the compacting chamber, the circulation of the compressed fluid to the outlet orifice is promoted.Since almost all the compressed fluid is sucked out, the loss of compressed fluid during the implementation of the method is limited, which makes it possible to reduce the amount of compressed fluid required.

[0020] According to another particular embodiment of the invention, the grooves are interconnected. Thus, the circulation of the compressed fluid in the grooves is improved, for example, in order to bring the compressed fluid to the outlet opening faster.

[0021] According to another specific embodiment of the invention, the grooves form a two-dimensional groove network. According to another specific embodiment of the invention, the grooves form a grid pattern. Thus, circulation of the compressed fluid in all directions can be obtained and the membrane is very easy to manufacture.

[0022] According to another particular embodiment of the invention, the membrane is reinforced with glass fibers or polyester fibers.

[0023] According to another particular embodiment of the invention, the compressed fluid comprises at least one oil. The invention is particularly advantageous in cases where the compressed fluid comprises oil or substances harmful to health or the environment, since this makes it possible to limit as much as possible the risk of interaction with the compressed fluid or of uncontrolled leakage of the compressed fluid outside the tool.

[0024] According to another particular embodiment of the invention, the impregnating fluid is a resin and the method further comprises a step of polymerizing the resin impregnating the fiber preform after the step of injecting the impregnating fluid and the compressed fluid and before the step of sucking the compressed fluid.

[0025] According to another particular embodiment of the invention, the fiber preform is made by three-dimensional weaving of fibers.Thus, since the fiber preform is intended to form a fiber reinforcement of a composite material part, the resulting composite material will have very good mechanical properties and a low risk of delamination.

[0026] The present invention also relates to a system for manufacturing a composite material component, the system comprising:

[0027] - a mould comprising an impregnation chamber comprising a support surface intended to come into contact with a first face of the preform, the impregnation chamber being closed by a flexible membrane situated opposite the support surface, said membrane separating the impregnation chamber from the compacting chamber,

[0028] - means for injecting an impregnation fluid comprising precursor matrix particles into the impregnation chamber,

[0029] - means for injecting a compressed fluid into the compaction chamber to exert pressure on the membrane,

[0030] - means for sucking the compressed fluid in the compacting chamber through one or more outlet openings,

[0031] The system is characterized in that the surface of the membrane located on the compacting chamber side comprises a plurality of grooves.

[0032] According to a particular embodiment of the invention, the groove is arranged so that when the membrane is in contact with the wall of the compacting chamber during operation of the suction device, at least a portion of the groove leads to at least one outlet hole of the compacting chamber or to a space of the compacting chamber comprising at least one outlet hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic cross-sectional view of a tool according to the invention with a fiber preform placed in the tool.

[0034] Figure 2 yes Figure 1 Schematic perspective view of a membrane of the tool.

[0035] Figure 3 yes Figure 2 A schematic partial cross-sectional view of a membrane showing three grooves in the cross-section.

[0036] Figure 4 yes Figure 1 Schematic cross-sectional view of a tool during injection of an impregnation fluid.

[0037] Figure 5 yes Figure 1 Schematic cross-sectional view of a tool during injection of compressed fluid.

[0038] Figure 6 yes Figure 1 Schematic cross-sectional view of a tool during the process of sucking compressed fluid. DETAILED DESCRIPTION

[0039] Figures 1 to 6 An exemplary system or tool for manufacturing a composite material component according to the invention is shown. The manufacturing system 200 comprises a mould comprising firstly an impregnation chamber 201 in which the fiber preform 10 is arranged and secondly a compacting chamber 202 .

[0040] The impregnation fluid 5 is intended to be injected into the impregnation chamber 201, while the compressed fluid 6 is intended to be injected into the compacting chamber 202. Therefore, the impregnation chamber 201 comprises one or more inlet holes 211, allowing the introduction of the impregnation fluid 5 into said impregnation chamber 201. The one or more inlet holes 211 of the impregnation chamber 201 may be equipped with a valve 211a. The impregnation chamber 201 may also comprise one or more outlet holes 212, allowing a portion of the impregnation fluid 5 to be removed. Similarly, the compacting chamber 202 comprises one or more inlet holes 221, allowing the introduction of the compressed fluid 6 into said compacting chamber 202, and one or more outlet holes 221, allowing the suction and removal of the compressed fluid 6 present in said compacting chamber 202. The inlet hole and the outlet hole 221 of the compacting chamber 202 may be coincident, or at least partially coincident, as in Figures 1 to 6 The embodiment shown in . One or more inlet holes 221 of the compacting chamber 202 may be equipped with a valve 221a.

[0041] The fiber preform 10 is intended to form the fiber reinforcement of the composite part to be manufactured. The fiber preform 10 is considered here to be the fiber structure of the composite part to be manufactured, obtained by any technique or combination of techniques for fabric construction, alignment and deformation in order to arrange it in the tool 200 .

[0042] Therefore, the preform 10 can be produced at least in part by stacking layers or folds obtained by two-dimensional weaving (2D). The preform 10 can also be made into a single piece directly by three-dimensional weaving (3D), or include at least one part made by three-dimensional weaving. "Two-dimensional weaving" here should refer to a conventional weaving method, in which each weft yarn passes from one side of the yarn of a single warp layer to the other side, or vice versa. The term "three-dimensional weaving" here should refer to weaving in which warp yarns are crossed with multiple layers of weft yarns or weft yarns are crossed with multiple layers of warp yarns. Therefore, a single weft yarn is interwoven with any multiple different warp yarn layers.

[0043] The preform 10 may also be made at least partially of a sheet of unidirectional fibers (UD), which may be obtained by depositing a tape or by automated fiber placement (AFP) or by filament winding.

[0044] The preform 10 may be made of ceramic fibers, carbon fibers, or a mixture of the two. Specifically, the preform 10 may be made of fibers composed of alumina, mullite, silica, aluminosilicate, borosilicate, silicon carbide, carbon, or a mixture of several of these materials. The preform 10 may contain any type of glass fiber, mixed or not mixed with other types of fibers.

[0045] The fiber preform 10 may be manufactured by a combination of multiple weaving methods or a combination of multiple materials, for example, unidirectional fiber sheets may be inserted between pleats produced by three-dimensional weaving.

[0046] The fiber preform 10 includes a first face 10 a and a second face 10 b opposite to the first face 10 a .

[0047] like Figures 1 to 6 In the embodiment shown in , the impregnation chamber 201 may include a filter layer 240 inserted between the fiber preform 10 and the one or more outlet holes 212 of the impregnation chamber 201. For example, when the impregnation fluid 5 is a slurry consisting of a liquid phase and precursor matrix particles, the filter layer 240 may retain the precursor matrix particles in the preform 10 while allowing the liquid phase of the slurry to pass. More generally, the filter layer 240 may retain the one or more matrix precursors in the fiber preform 10 and allow the remaining portion of the impregnation fluid 5 to pass, for example, so as to remove the remaining portion of the impregnation fluid through the outlet holes 212 of the impregnation chamber 201.

[0048] The filter layer 240 includes a first surface 240 a and a second surface 240 b opposite to the first surface 240 a. Preferably, the first surface 10 a of the preform 10 is located on the second surface 240 b of the filter layer 240 .

[0049] The filter layer 240 may be made of, for example, microporous polytetrafluoroethylene (PTFE), or may be made of gypsum or paper. To manufacture the filter layer 240, for example, a material having a pore size between 1 μm and 5 μm may be used. The filter layer 240 may have a pore size of 10 -14 m 2 and 10 -15 m 2 The final penetration rate between .

[0050] like Figures 1 to 6 In the embodiment shown in , when the tool includes a filter layer 240, the impregnation chamber 201 may also include a rigid perforated element 250, which is between the filter layer 240 and the one or more outlet holes 212 of the impregnation chamber 201. More precisely, the first face 250a of the rigid perforated element 250 is in contact with the wall of the impregnation chamber 201 opposite to the compaction chamber 202, or the rigid perforated element coincides with the wall of the impregnation chamber 201 opposite to the compaction chamber 202. The second face 250b of the rigid perforated element 250 opposite to the first face 250a can be in contact with the first face 240a of the filter layer 240, in other words, the first face 240a of the filter layer 240 is located on the second face 250b of the rigid perforated element. Such a rigid perforated element 250 is particularly described in document US20190134848A1. The function of the rigid perforated element 250 is to facilitate the removal of the liquid phase that has passed through the filter layer 240 through the one or more exit holes 212 , regardless of its exit point on the first face 240 a of the filter layer 240 .

[0051] To further facilitate the removal of part of the immersion fluid 5, the rigid perforated element may comprise cutouts or cavities 255 between its openings.

[0052] A distribution element (not shown) can optionally be arranged between the filter layer 240 and the rigid perforated element 250, the permeability of the distribution element being greater than the permeability of the filter layer 240. Such a distribution element makes it possible to make the flow rate of the liquid phase more uniform within the filter layer 240. Then, the first face of the distribution element rests against the second face of the element of the rigid perforated element 250b, and the second face of the distribution element opposite to the first face of the distribution element rests against the first face 240a of the filter layer 240.

[0053] The first face 10a of the preform 10 is in contact with the support surface of the impregnation chamber 201 and is located on the support surface of the impregnation chamber 201. Figures 1 to 6 In the embodiment shown, the support surface of the impregnation chamber corresponds to the second face 240b of the filter layer 240. Of course, it does not depart from the scope of the invention when the support surface of the impregnation chamber is a rigid wall of said impregnation chamber opposite to the compaction chamber, or one face of a rigid perforated element (as described above). Preferably, when the impregnation fluid 5 is a slurry comprising a liquid phase and precursor matrix particles, the first face 10a of the preform 10 is located on the filter or filter layer 240. Preferably, when the impregnation fluid is a resin, the first face 10a of the preform 10 is located on the wall of the impregnation chamber opposite to the compaction chamber, or on one face of a rigid perforated element (as described above).

[0054] The impregnation chamber 201 and the compaction chamber 202 of the mold are separated by a pliable film 230 (in other words, a flexible film 230). The flexible film 230 is placed opposite to the second face 10b of the preform 10. In the impregnation chamber 201, the flexible film 230 is preferably opposite to the support surface of the impregnation chamber 201. The film 230 includes a first surface 230a and a second surface 230b opposite to the first surface 230a. The first surface 230a of the film 230 is located opposite to the preform 10. The first surface 230a of the film 230 is located on the impregnation chamber 201 side, and the second surface 230b of the film 230 is located on the compaction chamber 202 side.

[0055] The membrane 230 may apply pressure to the impregnation fluid 5 in the impregnation chamber 201 so that the impregnation fluid 5 penetrates into the fiber preform 10. The membrane 230 may also apply compaction pressure to the fiber preform 10 in the impregnation chamber 201 to reduce the expansion of the preform. The pressure applied by the membrane 230 is generated by the compressed fluid 6, which deforms the membrane 230 toward the fiber preform 10 by applying pressure to the membrane 230. If the pressure in the impregnation chamber 201 increases, the pressure applied by the compressed fluid 6 to the membrane 230 may also keep the membrane 230 in a position close to the fiber preform 10. Therefore, when the compaction chamber 202 is filled with the compressed fluid 6, the first surface 230a of the membrane 230 may be in contact with the fiber preform 10. Therefore, the first surface 230a of the membrane 230 is preferably smooth. The first surface 230a of the membrane 230 may not have any grooves.

[0056] Preferably, if Figures 1 to 6 As shown, the film separates the first part 210 of the mold 200 from the second part 220 of the mold 200, which can correspond to the cover. Therefore, the first part 210 of the mold includes the one or more inlet holes 211 of the impregnation chamber 201, and includes the one or more possible outlet holes 212 of the impregnation chamber 201. The second part 220 of the mold 200 includes the one or more inlet holes 221 of the compaction chamber 202, and includes the one or more outlet holes 222 of the compaction chamber 202. Therefore, the first part 210 of the mold 200 and the film 230 define the impregnation chamber 201. Specifically, the inner wall of the first part 210 of the mold 200 and the first face 230a of the film 230 define the impregnation chamber 201. Similarly, the second part 220 of the mold 200 and the film 230 define the compaction chamber 202. The inner wall of the second part 220 of the mold 200 and the second face 230b of the film 230 define the compaction chamber 202. The compacting chamber 202 is thus delimited by an upper wall 202 a opposite the membrane 230 and two opposite side walls 202 b , 202 d connecting the upper wall 202 a to the membrane 230 .

[0057] The length of the film 230 is in the longitudinal direction D L The width is D in the transverse direction. T Extend upward, such as Figure 2 The thickness of the film 230 is in the thickness direction D E Upper extension, thickness direction D E Perpendicular to the longitudinal direction D L and transverse direction D T .

[0058] The membrane 230 is made of, for example, silicone, or of, for example, an elastomeric material such as rubber. The membrane 230 may be reinforced with glass fibers or polyester fibers. The membrane 230 must be made of a material that can withstand the temperatures that the membrane 230 may be subjected to during the entire method and the fluids that the membrane 230 will come into contact with. The membrane 230 must have a compressibility consistent with the dimensional tolerances required for the component. For example, the membrane 230 in the thickness direction D E The average thickness on the surface may be between 2 mm and 15 mm, and preferably in the thickness direction D E The average thickness on the fiber preform is between 3 mm and 7 mm. In the case of fiber preforms with complex geometries, such as fiber preforms with a concave shape, the thickness of the membrane can be increased locally to limit the amount of compressed fluid to be injected. For example, in order to adapt to specific points of the fiber preform, the thickness of the membrane can reach 30 mm.

[0059] According to the present invention, the membrane 230 comprises a plurality of grooves 235a, 235b on its second surface 230b. These grooves 235a, 235b are channels, grooves or furrows on the second surface 230b of the membrane 230. The grooves 235a, 235b do not open to the first surface 230a of the membrane 230, and therefore the grooves 235a, 235b do not open to the impregnation chamber 201. The grooves 235a, 235b have a sufficient width and depth to allow the one or more compressed fluids 6 to circulate inside the grooves 235a, 235b. The grooves may have a width and depth of several millimeters.

[0060] The grooves 235a, 235b may be grooves of rectangular cross-section with protruding edges, or grooves of rectangular cross-section with rounded edges 2350, referred to as "U-shaped" cross-sections, such as Figure 3 As shown. The grooves 235a, 235b may have a semicircular cross section. The cross section here belongs to a plane perpendicular to the membrane. The grooves 235a, 235b are preferably hollowed out in the thickness of the membrane 230. The thickness of the membrane 230 at the grooves 235a, 235b may be less than the portion of the membrane 230 extending between the grooves 235a, 235b.

[0061] A plurality of grooves 235a, 235b may form a network or a plurality of different networks. The grooves 235a, 235b may be interconnected. In particular, the grooves 235a, 235b may form a network covering at least a portion of the film 230. The grooves 235a, 235b may form a network covering a majority of the area of ​​the film 230. Therefore, the film 230 may include a discharge portion 232 having a plurality of grooves 235a, 235b and a smooth portion 231 not including any grooves. Preferably, the smooth portion 231 is located around the discharge portion 232. Preferably, the film 230 is assembled with the first portion 210 and the second portion 220 of the mold by the smooth portion 231, and the discharge portion 232 is in a free state when no pressure or suction is applied to the film 230. Preferably, the grooves 235a, 235b may extend over the entire free portion of the film 230, in other words, over the entire portion of the film 230 that is not fixed to the rigid portion of the mold 200.

[0062] The grooves 235a and 235b may form a grid. In other words, the first plurality of grooves 235a extend along a first direction, and the second plurality of grooves 235b extend along a second direction different from the first direction. Here, if the first direction and the second direction are not perpendicular, the grooves 235a and 235b are also considered to form a grid. Figure 2 and Figure 3 In the embodiment shown, the first plurality of grooves 235a are arranged along the longitudinal direction D L The second plurality of grooves 235b extend along the transverse direction D T Extension, wherein the longitudinal direction D L and transverse direction D T vertical. Therefore, Figure 2 and Figure 3 In the illustrated embodiment, the grooves 235a, 235b form a straight grid. In other words, the first plurality of grooves 235a and the second plurality of grooves 235b are arranged along a perpendicular direction D. L and D T extend.

[0063] The membrane 230 has grooves 235a, 235b forming a grid, enabling the compressed fluid 6 to circulate very efficiently, especially when the membrane 230 is pressed against the rigid walls of a mould, while being very easy to manufacture.

[0064] The arrangement of the grooves 235a, 235b on the second surface 230b of the membrane 230 is preferably adapted to the configuration of the compaction chamber 202 and the arrangement of the one or more outlet holes 221 for the compacted fluid 6. Thus, the grooves 235a, 235b may be arranged such that when the membrane 230 is in contact with the one or more outlet holes 221 of the compaction chamber 202 during the suction step, at least one groove 235a, 235b leads to at least one of the outlet holes 221 with which the membrane 230 is in contact.

[0065] The grooves may be arranged so that when the membrane 230 is in contact with one or more walls of the compacting chamber 202 comprising one or more outlet holes of the compacting chamber 202 during the suction step, the portion of the membrane 230 in contact with said one or more walls comprises a network of grooves 235a, 235b leading on the one hand to at least one of the outlet holes with which the membrane 230 is in contact and on the other hand to the space of the compacting chamber 202. Thus, the network of grooves comprises at least one path connecting one of the outlet holes with the space of the compacting chamber 202. Thus, due to the network of grooves, the impregnation fluid present in said space of the compacting chamber 202 can circulate to at least one outlet hole.

[0066] Furthermore, the grooves 235a, 235b may be arranged so that when the membrane 230 is in contact with one or more walls of the compacting chamber 202 that do not include an outlet hole during the suction step, the compacting chamber 202 is divided into at least two spaces separated by the membrane, and the portion of the membrane 230 in contact with the one or more walls includes a network of grooves that leads to one of the spaces of the compacting chamber 202 on the one hand and to the other space of the spaces of the compacting chamber 202 on the other hand. Thus, the network of grooves includes at least one path connecting the two spaces of the compacting chamber 202 that are separated by the membrane 230. Thus, the impregnation fluid present in one of the spaces of the compacting chamber 202 that do not include an outlet hole and that are closed by the membrane 230 can circulate to at least one space of the compacting chamber 202 that includes at least one outlet hole due to the network of grooves.

[0067] More generally, the grooves are arranged so that when the membrane 230 is in contact with the wall of the compacting chamber 202 during the suction step, at least a portion of the grooves opens into at least one outlet hole or into a space of the compacting chamber that includes at least one outlet hole. Thus, during the suction step, in particular when the membrane 230 is in contact with the outlet hole (e.g. Figure 6 As shown), or when the membrane 230 divides the compacting chamber 202 into at least two spaces (one of which does not include the outlet hole), the circulation of the impregnating fluid 5 to the outlet hole 221 is promoted.

[0068] Preferably, the bottom of the groove follows a direction relative to the longitudinal direction D L and lateral D T The immersion fluid may have an inclined trajectory in a plane of a direction, the trajectory being directed towards the at least one outlet opening to further promote the flow of the immersion fluid.

[0069] After placing the fiber preform 10 into the impregnation chamber 201, the first and second parts 210, 220 of the mold 200 and the film 230 are appropriately arranged as described above and as shown in FIG. Figure 1 shown.

[0070] like Figure 4As shown, the impregnation fluid 5 is injected into the impregnation chamber 201 via the one or more inlet holes 211 using an injection device for the impregnation fluid 5. The impregnation fluid 5 may be, for example, a slurry including precursor matrix particles, or a resin.

[0071] If the impregnation fluid 5 is a resin, it may be, for example, an epoxy resin, a carbon precursor resin or a silicon carbide precursor resin.

[0072] If the impregnation fluid 5 is a slurry, the slurry may correspond to a suspension containing a liquid phase and a powder of matrix precursor particles. The liquid phase may in particular consist of water, ethanol or any other liquid capable of suspending the desired powder. The pH of the liquid phase of the slurry may be adjusted according to the properties of the particles, for example, for alumina powder, the pH of water is acidic. An organic binder (for example, water-soluble PVP or PVA) may also be added. The binder may ensure the consistency of the raw materials, optionally after drying and before sintering. The slurry may correspond, for example, to an aqueous suspension consisting of alumina powder, wherein the average particle size (D50) of the alumina powder is between 0.1 μm and 1 μm, the volume fraction is between 5% and 50%, and the suspension is acidified by nitric acid (pH between 1.5 and 4). In addition to alumina, the refractory oxide particles may also be made of a material selected from alumina, mullite, silica, aluminosilicates, aluminophosphates, zirconium oxide, carbides, borides, nitrides and carbon. Depending on their basic composition, the refractory oxide particles can also be mixed with alumina, zirconia, aluminosilicates, rare earth oxides, rare earth disilicates (e.g. for environmental or thermal barriers) or any other filler able to add specific functionality to the final material (carbon black, graphite, silicon carbide, etc.).

[0073] Once the impregnation fluid 5 is injected into the impregnation chamber 201, the compressed fluid 6 is injected into the compaction chamber 202 through the one or more inlet holes 221 of the compaction chamber 202 using the injection device of the compressed fluid 6. Figure 5 The compressed fluid 6 may be water. However, the invention is particularly advantageous in the case where the compressed fluid 6 comprises at least one oil, and / or in the case where the compressed fluid 6 comprises substances that may be harmful to health or the environment.

[0074] The compressed fluid 6 applies pressure to the impregnating fluid 5 through the membrane 230, forcing the impregnating fluid 5 to penetrate into the fiber preform 10. The compressed fluid 6 applies pressure to the entire membrane 230, thereby applying pressure to the entire impregnating fluid 5 above the preform 10.

[0075] In the case where the impregnation fluid 5 is a slurry, it is preferred to reduce the pressure exerted by the membrane 230 on the slurry and the fiber preform in order to allow the slurry to penetrate into the preform 10 and to compact the preform 10 sufficiently so that the liquid phase of the slurry can be discharged through the filtration layer 240 without deteriorating the fiber preform 10. In combination with the pressure exerted on the slurry by the compressed fluid 6, pumping P can be performed at the one or more outlet openings 212 of the impregnation chamber 201, for example by a main vacuum pump ( Figure 5 200 ). The pumping is optional. Furthermore, the tool 200 may be equipped with heating means, for example resistance elements integrated into the walls of the first part 210 and the second part 220 of the mold 200, in order to increase the temperature in the compacting chamber 202 and promote the removal of the liquid in the slurry by evaporation. The filter layer 240 enables the precursor matrix particles present in the slurry to be retained, so that the particles are gradually deposited in the fiber preform 10. This makes it possible to obtain a matrix later, for example after sintering.

[0076] When the fiber preform 10 is properly impregnated, a heating or heat treatment step may be performed. For example, in the case where the impregnation fluid 5 is a resin, a step of polymerizing the resin may be performed by heating the fiber preform 10 impregnated with the resin. Preferably, the step of polymerizing the resin is performed while the compressed fluid 6 in the compacting chamber 202 continues to maintain the pressure on the membrane 230, thereby maintaining the pressure on the fiber preform 10.

[0077] Then, a discharge step is performed, in which the compressed fluid 6 in the compacting chamber 202 is sucked through the one or more outlet holes 221 of the compacting chamber 202 using the suction device A, such as Figure 6 shown.

[0078] exist Figures 1 to 6 In the embodiment shown, the inlet and outlet openings 221 of the compacting chamber 202 are located on the upper wall 202 a of the chamber 202 opposite the membrane 230 .

[0079] When the outlet hole and the inlet hole of the compacting chamber 202 do not coincide with each other, compressed air can be introduced through the one or more inlet holes of the compacting chamber 202. Preferably, if the one or more inlet holes of the compacting chamber 202 and the one or more outlet holes of the compacting chamber 202 do not coincide with each other, the one or more inlet holes are far away from the one or more outlet holes. For example, the one or more inlet holes may be arranged on a first edge of an upper wall 202a of the compacting chamber 202, and the one or more outlet holes may be arranged on a second edge of the upper wall 202a opposite to the first edge. According to another embodiment, the one or more inlet holes may be arranged on a first side wall 202b of the compacting chamber 202, the first side wall 202b connecting the upper wall 202a of the compacting chamber 202 with the membrane 230, and the one or more outlet holes may be arranged on a second side wall 202c of the compacting chamber 202 opposite to the first side wall 202b.

[0080] Due to the suction, the membrane 230 may come into contact with one or more rigid walls 202a of the mold 200, more precisely, with one or more rigid walls 202a of the compacting chamber 202. The presence of the grooves 235a, 235b on the second surface 230b of the membrane 230 may force the impregnation fluid 5 to be present at a localized location on the membrane 230. The presence of the grooves 235a, 235b on the second surface 230b of the membrane 230 may also cause the impregnation fluid 5 to circulate between the membrane 230 and the one or more walls of the impregnation chamber 202 against which the membrane 230 is pressed. This makes it easier for at least a portion of the impregnation fluid 5 to reach the one or more outlet holes 221 of the compacting chamber 202.

[0081] Finally, the impregnated or densified preform is taken out of the impregnation chamber 201 and then processed in a well-known manner to obtain the desired component. The resulting component is, for example, a ceramic matrix composite (CMC) component or an organic matrix composite (OMC) component. According to the method of the present invention, for example, an aircraft engine shell or an aviation rear fuselage component can be manufactured.

[0082] The expression “between… and…” should be understood as including both endpoint values.

Claims

1. A method for manufacturing a composite material component, the method comprising the following steps: - arranging the fiber preform (10) in a mold, the mold comprising an impregnation chamber (201), the first face (10a) of the preform (10) being located on a support surface (240b) of the impregnation chamber (201), the impregnation chamber (201) being closed by a flexible membrane (230) located opposite the second face (10b) of the preform (10), said membrane (230) separating the impregnation chamber (201) from the compacting chamber (202), - injecting the impregnation fluid (5) into the impregnation chamber (201), - injecting a compressed fluid (6) into the compacting chamber (202) to exert pressure on the membrane (230), - sucking the compressed fluid (6) present in the compacting chamber (202) through one or more outlet openings (221) of the compacting chamber (202), The method is characterized in that a surface (230b) of the membrane (230) on the compacting chamber (202) side includes a plurality of grooves (235a, 235b).

2. A method according to claim 1, wherein the grooves (235a, 235b) are arranged so that when the membrane (230) is in contact with the wall (202a, 202b, 202c) of the compacting chamber (202), at least a portion of the grooves (235a, 235b) leads to at least one outlet hole (221) of the compacting chamber (202) or to a space in the compacting chamber including at least one outlet hole.

3. The method according to claim 1 or 2, wherein the grooves (235a, 235b) are interconnected.

4. The method according to any one of claims 1 to 3, wherein the grooves (235a, 235b) form a two-dimensional groove network. The method according to claim 4 , wherein the grooves ( 235 a , 235 b ) form a grid.

6. The method according to any one of claims 1 to 5, wherein the membrane (230) is reinforced with glass fibers or polyester fibers.

7. Method according to any one of claims 1 to 6, wherein the compressed fluid (6) comprises at least one oil.

8. The method according to any one of claims 1 to 7, wherein the impregnating fluid (5) is a resin, the method further comprising a step of polymerizing the resin impregnating the fiber preform (10) after the step of injecting the impregnating fluid (5) and the compressed fluid (6) and before the step of sucking the compressed fluid (6).

9. The method according to any one of claims 1 to 8, wherein the fiber preform (10) is produced by three-dimensional weaving of fibers.

10. A system (200) for manufacturing a composite material component, the system comprising: - a mould comprising an impregnation chamber (201) comprising a support surface (240b) intended to come into contact with the first face (10a) of the preform (10), the impregnation chamber (201) being closed by a flexible membrane (230) situated opposite the support surface (240b), said membrane (230) separating the impregnation chamber (201) from the compacting chamber (202), - means for injecting an impregnation fluid (5) into the impregnation chamber (201), - means for injecting a compressed fluid (6) into the compacting chamber (202) in order to exert pressure on the membrane (230), - means for sucking the compressed fluid (6) present in the compacting chamber (202) via one or more outlet openings (221), The system (200) is characterized in that the surface of the membrane (230) located on the compacting chamber (202) side includes a plurality of grooves (235a, 235b).

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