Bladed wheel sector with infill sections

Abstract

Bladed wheel sector with filling portions. The invention relates to a method for manufacturing a bladed wheel sector (300) comprising an inner platform (310), an outer platform (320), and one or more aerodynamic profiles (330), comprising: - the arrangement of a fibrous blank (111) in a mold (510) comprising one or more grooves (512), - the injection of a filling material (112) so as to fill the grooves (512) of the mold (510), - the heat treatment of the blank (111) and the injected filling material (112) so as to obtain a first platform preform (210), - the assembly of the first platform preform (210) with one or more aerodynamic profile preforms (230) and a second platform preform (220) to obtain a fibrous assembly (200), - densification by a matrix of the fibrous assembly (200) so as to obtain said bladed wheel sector (300). Figure for the abbreviation: Fig. 8

Description

Title of the invention: Bladed wheel sector with filling portions. Technical field.

[0001] The present invention relates to the manufacture of turbine blades, and more particularly to the manufacture of rectifier blades. Such blades are conventionally manufactured in a bladed wheel sector. Previous technique

[0002] Stator blades are conventionally formed by an aerodynamic profile connecting an inner platform to an outer platform. Currently, stator blades are made of metal, particularly titanium. It is now preferable to manufacture stator blades from composite materials, and especially from organic matrix composites (OMCs). Indeed, OMCs are lighter than most metals while maintaining good mechanical properties. Thus, their use helps to optimize the performance of turbomachinery or turbomachinery equipment, notably by reducing the overall mass of the turbomachine. The efficiency of the turbomachine is thereby improved, leading to reduced fuel consumption and consequently a reduction in harmful emissions (CO, CO2, NOx, etc.).Thus, organic matrix composite (OMC) materials are already used for blower blades, as described in document FR 3 068 640.

[0003] However, obtaining the optimal amount of material at the junction between the airfoil and the platforms is difficult. Indeed, the radius between the airfoil and the platforms may lack material or have an unsatisfactory material quality.

[0004] In addition, it is desirable that the junction portion between the aerodynamic profile and the platforms has an evolving cross-section: indeed, it is preferable that the junction portion be thick in the center and thinner towards the ends of said junction portion, in order to better follow the shape of the aerodynamic profile. Description of the invention

[0005] The invention aims to provide a solution for obtaining a satisfactory quantity and quality of material at the radius between the aerodynamic profile and the platforms.

[0006] To this end, the invention proposes a method for manufacturing a bladed wheel sector made of organic matrix composite material, said sector comprising a an internal platform, an external platform and one or more aerodynamic profiles extending radially between the two platforms, the method comprising:

[0007] - the arrangement of a first fibrous platform blank in a mold presenting an impression, the impression comprising a main portion having the shape of one of the platforms to be produced and one or more grooves extending in the same direction of extension, the groove(s) comprising one or more injection ports, the first fibrous platform blank being placed in the main portion of the impression,

[0008] - the injection of a filling material through the injection port(s) so as to fill the grooves in the mold,

[0009] - the heat treatment of the first fibrous platform blank and of the injected filling material to obtain a first preform of one of the platforms to be created, comprising protruding filling portions extending along the direction of extension,

[0010] - the demolding of the first preform of one of the platforms to be produced,

[0011] - the assembly of the first preform of one of the platforms to be produced with a or several preforms of aerodynamic profiles and a second preform of the other platform to be produced in order to obtain a fibrous assembly having the shape of the bladed wheel sector to be obtained, the aerodynamic profile preform(s) extending radially between the first preform and the second platform preform, the filling portion(s) extending axially so that each filling portion is covered by one or more aerodynamic profile preforms,

[0012] - the densification by a matrix of the fibrous assembly having the shape of the sector of bladed wheel to be obtained so as to obtain said bladed wheel sector in composite material.

[0013] Such a manufacturing process makes it easy to obtain sufficiently filled junctions between the aerodynamic profile and the platforms, resulting in good material quality. The use of overmolding allows for easy automation of the process and excellent repeatability. Furthermore, overmolding provides considerable freedom in shaping the infill, thus easily enabling the creation of a variable cross-section along the axial direction.

[0014] According to a particular embodiment of the invention, the manufacture of the second preform of the other platform to be produced comprises:

[0015] - the arrangement of a second fibrous platform blank in a mold presenting an imprint, the imprint comprising a main portion having the shape of the other platform to be produced and one or more grooves extending in the same direction of extension, the groove(s) comprising one or more ports injection, the second fibrous platform blank being arranged in the main portion of the impression,

[0016] - the injection of a filling material through the injection port(s) so as to fill the grooves in the mold,

[0017] - the heat treatment of the second fibrous platform blank and of the injected filler material to obtain the second preform comprising protruding filler portions extending along the direction of extension,

[0018] - the demolding of the second platform preform;

[0019] the assembly of the second platform preform with the first platform preform and the airfoil preforms being carried out so that each airfoil preform connects one of the filling portions of the first preform to one of the filling portions of the second preform, the filling portion or portions of the second preform extending axially so that each filling portion of the second preform is covered by one or more airfoil preforms.

[0020] According to another particular embodiment of the invention, the first platform blank, and where applicable the second platform blank, is made by superimposing pre-impregnated plies.

[0021] Due to the geometry of the bladed wheel sector to be produced, it is preferable to integrate the resin before assembling the fiber assembly. Indeed, injecting resin into the already assembled dry fiber assembly afterward is difficult to perform.

[0022] According to another particular embodiment of the invention, the cross-section of the grooves of the mold is variable according to the direction of extension, so as to obtain filling portions having a cross-sectional area that varies according to the direction of extension.

[0023] Indeed, the process of the invention makes it possible to produce filling portions with an adaptable geometry. Thus, the geometry of the filling portions can be adapted to follow the geometry of the aerodynamic profiles.

[0024] According to another particular embodiment of the invention, the filling material is a thermoplastic material and in which the first fibrous platform blank, the aerodynamic profile preforms and where applicable the second fibrous platform blank are impregnated with a thermoplastic resin.

[0025] According to another particular embodiment of the invention, the filling material is a thermosetting material in which the first fibrous platform blank, the aerodynamic profile preforms and, where applicable The second fiber platform blanks are impregnated with a thermosetting sand resin.

[0026] According to another particular embodiment of the invention, the filling material is loaded with carbon particles.

[0027] Thus, the viscosity of the filling material is better controlled, which facilitates the injection of an appropriate quantity of material and makes it possible to avoid an excess or an unwanted flow of the filling portions.

[0028] According to another particular embodiment of the invention, the aerodynamic profile preforms have a "C" shape, a pair of aerodynamic profile preforms placed back to back forming the fibrous reinforcement of a single aerodynamic profile of the bladed wheel sector to be produced, the filling portions being arranged between two aerodynamic profile preforms belonging to the same pair.

[0029] According to another particular embodiment of the invention, the manufacture of the aerodynamic profile preforms comprises:

[0030] - the production of a fibrous rough aerodynamic profile by superimposing pre-impregnated folds,

[0031] - shaping the fibrous blank of the aerodynamic profile by means of a membrane placed under vacuum to give a "C" shape to the fibrous rough aerodynamic profile, then

[0032] - the pre-consolidation of the shaped aerodynamic profile fibrous blank so as to obtain the aerodynamic profile fibrous preform.

[0033] The invention further relates to a sector of a bladed wheel obtained according to the manufacturing process as described above.

[0034] The invention also relates to a bladed wheel comprising a plurality of sectors made according to the manufacturing process described above. Brief description of the drawings

[0035] [Fig-1] The [Fig.1] is a schematic cross-sectional view of a sector of a bladed wheel.

[0036] [Fig.2] Fig.2 is a schematic cross-sectional view of a mold and a counter- mold for manufacturing a fibrous platform preform.

[0037] [Fig.3] The [Fig.3] is a schematic perspective view of the mold of the [Fig.2].

[0038] [Fig.4] Fig.4 is a schematic cross-sectional view of the mold of Figures 2 and 3 in into which a fibrous platform blank is positioned.

[0039] [Fig. 5] Fig. 5 is a schematic cross-sectional view of the mold of Figures 2 to 4 in into which a filling material is injected.

[0040] [Fig. 6] Fig. 6 is a schematic perspective view of a fibrous preform of platform.

[0041] [Fig. 7] [Fig. 7] is a schematic cross-sectional view of a profile fibrous blank aerodynamic shaping on a mandrel.

[0042] [Fig.8] The [Fig.8] is a schematic cross-sectional view of the assembly of the fibrous platform preforms and the fibrous aerodynamic profile preforms to obtain the bladed wheel sector of the [Fig.1]. Description of the implementation methods

[0043] Figure 1 illustrates an example of a bladed wheel sector 300 achievable by the method of the invention. The bladed wheel sector 300 conventionally comprises an inner platform 310 and an outer platform 320 extending in a circumferential direction Dc around an axial direction DA. The bladed wheel sector 300 comprises one or more aerodynamic profiles 330, each extending between the two platforms 310 and 320 in a radial direction DR perpendicular to the axial direction DA. The aerodynamic profiles 330 correspond to blades.

[0044] The bladed wheel sector 300 achievable by the process of the invention can comprise a single aerodynamic profile: the bladed wheel sector 300 will then be comparable to a blade equipped with an internal platform and an external platform.

[0045] In the example illustrated in [Fig. 1], the bladed wheel sector 300 comprises three aerodynamic profiles. However, the invention remains within the scope of the invention if the bladed wheel sector comprises a different number of aerodynamic profiles. In particular, the invention is especially relevant for producing bladed wheel sectors comprising between 10 and 15 sectors. The invention is also particularly relevant for producing bladed wheel sectors corresponding to one-sixth of the total bladed wheel to be produced, that is, for bladed wheel sectors extending circumferentially over 60°.

[0046] Figures 2 and 3 illustrate an example of a mold 510 for implementing the process of the invention. The mold 510 can be associated with a counter-mold 520.

[0047] The mold 510 includes a cavity having the shape of one of the platforms to be produced. The cavity of the mold 510 includes a main portion 511. The main portion 511 of the cavity includes a bottom 51a. The main portion 511 of the cavity extends in depth along a depth direction DP. The main portion 511 of the cavity extends in depth to the bottom 511a along the depth direction DP. The main portion 511 of the cavity extends along a length direction DL between a first lateral edge and a second lateral edge. The main portion 511 of the cavity extends along an extension direction DE between a first longitudinal edge and a second longitudinal edge. The extension direction DE is perpendicular to the length direction DL. The extension direction DE is perpendicular to the depth direction DP. The length direction DL is preferably circumferential. Thus, the main portion 511 of the imprint preferably has a slightly curved shape along the length direction DL.

[0048] The mold cavity 510 further includes grooves 512. The grooves 512 extend along the extension direction DE. The grooves 512 are formed in the bottom 51la of the main portion 511 of the mold cavity 510. Preferably, the grooves 512 extend from the first longitudinal edge to the second longitudinal edge of the main portion 511. The grooves 512 comprise, along the extension direction DE, a first end 512a, then a central portion 512b, and then a second end 512a. The grooves 512 are cut into the bottom 51la of the main portion 511. The grooves 512 extend in depth along the depth direction DP. The grooves 512 include a groove bottom. Thus, the grooves 512 extend in depth to the groove bottom. The grooves 512 extend in width along the length direction DL.

[0049] The grooves 512 may have a constant cross-section along the extension direction DE. However, preferably, the grooves 512 have a variable cross-section along the extension direction DE. Preferably, the cross-sectional area of ​​the grooves 512 is smaller at the ends 512a than in the central portion 512b.

[0050] The maximum depth of the grooves 512 along the depth direction DP can remain constant along the extension direction DE, even if the section of the grooves 512 varies along the extension direction DE.

[0051] The grooves 512 may have a constant width along the length direction DL at the junction between the main portion 511 and the grooves 512 along the extension direction DE. The bottoms of the grooves 512 may have a variable width along the length direction DL along the extension direction DE. In particular, it is preferable that the grooves 512 be wider at the ends 512a of said grooves 512 than in the central portion 512b of said grooves 512 along the extension direction DE.

[0052] The mold 510 further includes injection ports 513 opening into grooves 512. Each groove 512 is associated with at least one injection port 513. In order to facilitate injection via the injection ports 513, the injection ports 513 preferably extend along the depth direction DP.

[0053] The main portion 511 of the mold cavity 510 is intended to receive a fibrous blank of one of the platforms to be produced. The grooves 512 are intended to allow the formation of the filling portions.

[0054] The mold 510 conventionally comprises as many ribs 512 as there are desired aerodynamic profiles, in other words, blades, on the bladed wheel sector 300 to be produced. Thus, the number of grooves conventionally corresponds to the number of aerodynamic profiles, that is to say, the number of blades, desired.

[0055] Thus, the method according to the invention comprises arranging a fibrous platform blank 111 in the mold 510, as illustrated in [Fig. 4]. The fibrous platform blank 111 is arranged in the main portion 511 of the cavity. The fibrous platform blank 111 rests against the bottom 51a of the main portion 511. The fibrous platform blank 111 is in contact with the bottom 511a of the main portion 511 of the cavity.

[0056] The mold 510 is closed by the counter-mold 520. Preferably, the mold 510 is closed by the counter-mold 520 so that the counter-mold 520 exerts pressure on the fibrous blank of platform 111.

[0057] The fibrous platform blank 111 is preferably obtained by layering pre-impregnated plies. Of course, it does not depart from the scope of the invention if the fibrous platform blank 111 is obtained by layering dry plies. Nor does it depart from the scope of the invention if the fibrous platform blank 111 is produced by another means.

[0058] The fibers of the platform fiber blank 111 are preferably made of carbon. It is of course not outside the scope of the invention if the fibers of the platform fiber blank 111 are made of glass. Nor is it outside the scope of the invention if the fibers of the fiber blank are made of a material mixture comprising at least two materials from: carbon, glass, or a ceramic.

[0059] In the case where the fibrous platform blank 111 is pre-impregnated, it may be pre-impregnated with a thermosetting or thermoplastic resin. The fibrous platform blank 111 may, for example, be pre-impregnated with an epoxy resin, a polyimide (PI), or a bismaleimide (BMI) resin. If the fibrous platform blank 111 is pre-impregnated with a thermoplastic material, it may, for example, be pre-impregnated to obtain a matrix of polyaryletherketone (PAEK), polyetherketoneketone (PEKK), polyetheretherketone (PEEK), polyetherimide (PEI), polyphenylene sulfide (PPS), polyethersulfone (PESU), or polycarbonate (PC).

[0060] Next, a filler material 112 is injected into the grooves 512 of the mold 510, as illustrated in [Fig. 5]. The filler material 112 fills the grooves 512 of the mold 510. Preferably, the counter-mold 520 maintains pressure on the fibrous platform blank 111 during the injection of the filler material 112.

[0061] The filler material 112 may be a thermoplastic or thermosetting material. If the fiber platform blank 111 is pre-impregnated with a thermosetting material, the filler material 112 will also preferably be a thermosetting material. Similarly, if the fiber platform blank 111 is pre-impregnated with a thermoplastic material, the filler material 112 will also preferably be a thermoplastic material. In general, it is preferable that the filler material 112 be identical or similar to the material pre-impregnating the fiber platform blank 111.

[0062] The filling material 112 can be filled. For example, the filling material 112 can be filled with fibers or particles. Indeed, it is desirable that the viscosity of the filling material 112 be controlled in order to obtain satisfactory filling portions. In particular, the filling material 112 can be filled with carbon fibers or particles, or with nanomaterial particles.

[0063] The injection of the filling material 112 is preferably carried out by controlling the temperature and pressure of the mold 510.

[0064] The mold 510 can be heated and pressurized so as to perform a heat treatment of the injected filling material 112 and of the fibrous platform blank 111.

[0065] A fibrous preform of platform 210 is thus obtained as illustrated in [Fig. 6]. The fibrous preform of platform 210 is removed from the mold 510.

[0066] The fibrous platform preform 210 comprises a main body 211 and filler portions 212 projecting from the main body 211. The main body 211 corresponds to the fibrous platform blank 111. Thus, the main body 211 was formed in the main portion 511 of the mold 510. The filler portions 212 correspond to the filler material 112 injected into the grooves 512. Thus, the filler portions 212 were formed in the grooves 512 of the mold 510.

[0067] The main body 211 of the fibrous platform preform 210 extends lengthwise and widthwise along the extension direction DE and the length direction DL. The main body 211 of the fibrous platform preform 210 extends in thickness along the depth direction DP. Preferably, the main body 211 is curved along the length direction DL.

[0068] The filling portions 212 extend along the extension direction DE. The filling portions 212 can extend over the entire width of the fibrous platform preform 210 along the extension direction DE. The filling portions 212 comprise, along the extension direction DE, a first end 212a, then a central portion 212b, then a second end 212a. The infill portions 212 project from the main body 211 along the depth direction DP. The infill portions 212 include a vertex. The vertices of the infill portions 212 correspond to the parts of the infill portions 212 formed at the bottoms of the grooves 512. Thus, the infill portions 212 extend vertically to the vertex. The infill portions 212 extend horizontally along the length direction DL.

[0069] The filling portions 212 may have a constant cross-section along the extension direction DE. However, preferably, the filling portions 212 have a variable cross-section along the extension direction DE, as illustrated in [Fig. 6]. Preferably, the cross-sectional area of ​​the filling portions 212 is smaller at the ends 212a than in the central portion 212b.

[0070] The maximum height of the filling portions 212 along the depth direction DP can remain constant along the extension direction DE, even if the section of the filling portions 212 varies along the extension direction DE.

[0071] The infill portions 212 may have a constant width along the length direction DL at the junction between the main body 211 and the infill portions 212 along the extension direction DE. The vertices of the infill portions 212 may have a variable width along the length direction DL along the extension direction DE. In particular, it is preferable that the infill portions 212 be narrower at the ends 212a of said infill portions 212 than in the central portion 212b of said infill portions 212 along the extension direction DE.

[0072] The fibrous preform of the platform 210 conventionally comprises as many filling portions 212 as there are desired aerodynamic profiles, in other words, blades, on the bladed wheel sector 300 to be produced. Thus, the number of filling portions 212 conventionally corresponds to the desired number of aerodynamic profiles, that is, the number of blades.

[0073] The fibrous preform of platform 210 can be used to produce the inner or outer platform of the bladed wheel sector to be manufactured. It thus constitutes the first fibrous preform of platform 210, obtained from a first fibrous blank of platform 111. The fibrous preform of platform 220 of the other platform can be manufactured in a similar manner to that described above, from a second fibrous blank of platform. It constitutes the second fibrous preform of platform 220. Thus, both fibrous preforms of platform 210 and 220 can be manufactured according to the process described above. For the remainder of this description, the first fibrous preform of platform 210 is intended to form the internal platform of the bladed wheel sector to be obtained and the second fibrous preform of platform 220 is intended to form the external platform of the bladed wheel sector to be obtained.

[0074] In particular, the two fibrous platform preforms 210 and 220 are made of the same material. The two fibrous platform preforms 210 and 220 are made with fibers of the same type and dimensions. The two fibrous platform preforms 210 and 220 are impregnated with the same resin.

[0075] Preferably, the filling portions of the first fibrous platform preform 210 have different dimensions from the filling portions of the second fibrous platform preform 220. Thus, the dimensions of the filling portions can be adapted to the shape of the aerodynamic profile. Indeed, the shape of the aerodynamic profile is typically different between the junction with the outer platform and the junction with the inner platform.

[0076] Similarly, the thickness of the main body 211 of the first platform fiber preform 210 along the depth direction DP will preferably be different from the thickness of the main body of the second platform fiber preform 220 along the depth direction DP. For example, the main body 211 of the first platform fiber preform 210, intended to form the inner platform, may be thicker than the main body of the second platform fiber preform 220, intended to form the outer platform. In the case where the first platform fiber preform 111 and the second platform fiber preform are formed by overlapping plies, the number of plies in the first fiber preform may be different from that in the second fiber preform.For example, the second fiber platform blank may comprise a number of plies between 40% and 60% of the number of plies of the first fiber platform blank 111. For example, the second fiber platform blank may comprise 6 plies and the first fiber platform blank 111 may comprise 12 plies.

[0077] The fibrous preforms of the aerodynamic profiles of the bladed wheel sector 300 to be obtained are made from fibrous blanks of aerodynamic profile 130, as illustrated in [Fig.7].

[0078] The fibrous blank of the aerodynamic profile 130 is preferably obtained by superimposing pre-impregnated plies. Of course, it does not depart from the scope of the invention if the fibrous blank of the aerodynamic profile 130 is obtained by superimposing dry plies. Nor does it depart from the scope of the invention if the fibrous blank of the aerodynamic profile 130 is produced by another means.

[0079] Preferably, the aerodynamic profile fiber blanks 130 are made of the same material as the two platform fiber preforms 210 and 220. The aerodynamic profile fiber blanks 130 are made with fibers of of the same nature and of the same dimensions as the two fibrous platform preforms 210 and 220. The fibrous blanks of aerodynamic profile 130 are made with the same resin as the fibrous blanks of platform 111.

[0080] The aerodynamic airfoil blank 130 can be shaped on a mandrel 601. The aerodynamic airfoil blank 130 is shaped to obtain an aerodynamic airfoil preform 230. The aerodynamic airfoil preform 230 preferably has a "C" shape. The "C" can be rounded with a variable radius of curvature, even a very small one, on the order of a millimeter, or even at right angles.

[0081] As illustrated in [Fig.7], the fiber blank of the aerodynamic profile 130 is thus shaped on the mandrel 601 so as to bend the fiber blank 130 at its ends 130a, on either side of a central portion 130b of the fiber blank 130. The ends 130a of the fiber blank of the aerodynamic profile 130 are bent on the same side, so as to obtain a "C" shape.

[0082] The shaping of the aerodynamic airfoil blank 130 into an aerodynamic airfoil preform 230 can be facilitated by the use of a sheet 602. In particular, the sheet 602 can be placed under vacuum to facilitate the shaping of the aerodynamic airfoil blank 130. This fibrous preform is heated prior to vacuum pulling to lower its viscosity and facilitate forming. The heating can be carried out using infrared radiant heating or any other heating method.

[0083] The shaped fibrous airfoil blank 130 is then pre-consolidated to obtain the fibrous airfoil preform 230. Pre-consolidation is conventionally carried out by heat treatment. In the case of a preform with a thermosetting matrix, the matrix remains with a very low degree of transformation after the shaping step, in order to maintain its full development at low viscosity during the assembly step.

[0084] This yields a fibrous preform with an aerodynamic profile 230 comprising a central portion 230b from which two end portions 230a extend, as illustrated in [Fig. 8]. The end portions 230a extend towards the same side from the central portion 230b so as to obtain the shape of "C".

[0085] When all the fibrous preforms 210, 220, 230 necessary for the production of the bladed wheel sector 300 have been produced, the said fibrous preforms 210, 220, 230 are assembled in order to obtain a fibrous assembly.

[0086] Fig. 8 illustrates an example of a fiber assembly 200 made by assembling two platform fiber preforms 210 and 220 and six aerodynamic profile fiber preforms 230. The fiber assembly has the shape of the bladed wheel sector 300 to be produced.

[0087] The fibrous platform preforms 210 and 220 are oriented such that the extension direction DE corresponds to the axial direction DA of the bladed wheel sector 300 to be produced. Similarly, the fibrous platform preforms 210 and 220 are oriented such that the depth direction DP and the length direction DL correspond respectively to the radial direction DR and the circumferential direction Dc of the bladed wheel sector 300 to be produced.

[0088] According to a particularly interesting configuration illustrated in [Fig. 8], the aerodynamic airfoil preforms 230 are assembled in pairs to form the airfoils. Each pair of aerodynamic airfoil preforms 230 comprises a first aerodynamic airfoil preform 231 and a second aerodynamic airfoil preform 232. Each first aerodynamic airfoil preform 231 is thus positioned back-to-back with the second aerodynamic airfoil preform 232 belonging to the same pair. The central portion 230b of each first aerodynamic airfoil preform 231 is thus in contact with the central portion 230b of the second aerodynamic airfoil preform 232 belonging to the same pair.The end portions 230a of the first aerodynamic profile fibrous preforms 231 are all oriented in the same first direction with respect to the circumferential direction Dc and the end portions 230a of the second aerodynamic profile fibrous preforms 232 are all oriented in the same second direction opposite to the first direction.

[0089] Thus, each pair of aerodynamic profile fiber preforms 230 has an "H" shape. Consequently, each pair of aerodynamic profile fiber preforms 230 has a trunk formed by the central portions 230b, from the upper end of which extend two legs and from the lower end of which extend two other legs, each leg being formed by an end portion 230a. The pairs of aerodynamic profile fiber preforms 230 are arranged such that one of the filling portions 212 of the first platform fiber preform 210 is located between two legs at the upper end of the "H" and one of the filling portions of the second platform fiber preform 220 is located between two legs at the lower end of the "H". The filling portions are each in contact with two legs belonging to the same "H".

[0090] Each aerodynamic profile fiber preform 230 is assembled so as to connect the first platform fiber preform 210 to the second platform fiber preform 220. Thus, each aerodynamic profile fiber preform 230 is in contact with the first platform fiber preform 210 and the second platform fiber preform 220. One of the end portions 230a of each aerodynamic profile fiber preform 230 is in contact with the first platform fiber preform 210 and the other end portion 230a of each aerodynamic profile fiber preform 230 is in contact with the second platform fiber preform 220. Each aerodynamic profile fiber preform 230 is in contact with one of the filling portions of the first platform fiber preform 210 and with one of the filling portions of the second platform fiber preform 220.

[0091] Each pair of aerodynamic profile fiber preforms 230 covers one of the filling portions 212 of the first platform fiber preform 210 and covers one of the filling portions of the second platform fiber preform 220. Preferably, each pair of aerodynamic profile fiber preforms 230 completely covers one of the filling portions 212 of the first platform fiber preform 210 and completely covers one of the filling portions of the second platform fiber preform 220. Each filling portion is arranged between the first platform fiber preform 210 and the second platform fiber preform 220 of the same pair of platform fiber preforms. The filling portions are arranged so as to be in contact with the junction between the central portion 230b and one of the end portions 230a of the aerodynamic profile fibrous preforms 230.

[0092] The resulting fibrous assembly 200 is then subjected to heat treatment to crosslink or consolidate the matrix. If the fibrous assembly 200 is formed from fibrous preforms 210, 220, 230 already impregnated with a matrix precursor, the heat treatment is carried out directly. If the fibrous assembly 200 is formed from fibrous preforms 210, 220, 230 without resin, it is possible to inject a resin into the fibrous assembly 200 after its formation.

[0093] The heat treatment of the fibrous assembly 200 is preferably carried out by applying pressure to said fibrous assembly 200, for example by means of an assembly of blocks around the fibrous assembly 200.

[0094] When the matrix is ​​formed in the pores of the fibrous assembly 200, a bladed wheel sector 300 is obtained as illustrated in [Fig. 1]. The bladed wheel sector 300 is intended to be assembled with other bladed wheel sectors to obtain a complete bladed wheel. Such a bladed wheel is intended to be installed in an aircraft turbomachine.

Claims

Demands

1. A method for manufacturing a bladed wheel sector (300) made of organic matrix composite material, said sector (300) comprising an inner platform (310), an outer platform (320), and one or more aerodynamic profiles (330) extending radially between the two platforms (310, 320), the method comprising: - placing a first fibrous platform blank (111) in a mold (510) having an impression, the impression comprising a main portion (511) having the shape of one of the platforms (310, 320) to be produced and one or more grooves (512) extending along the same extension direction (ED), the groove(s) (512) comprising one or more injection ports (513), the first fibrous platform blank (111) being placed in the main portion (511) of the impression, - injecting a filling material (112) through the injection port(s) (513) so as to fill the grooves (512) of the mold (510),- the heat treatment of the first fiber platform blank (111) and the injected filler material (112) to obtain a first preform (210) of one of the platforms (310, 320) to be produced, comprising protruding filler portions (212) extending along the extension direction (DE), - the demolding of the first preform (210) of one of the platforms (310, 320) to be produced, - the assembly of the first preform (210) of one of the platforms (310, 320) to be produced with one or more aerodynamic profile preforms (230) and a second preform (220) of the other platform (310, 320) to be produced in order to obtain a fibrous assembly (200) having the shape of the bladed wheel sector (300) to be obtained, the aerodynamic profile preform(s) (230) extending radially between the first preform (210) and the second preform (220) of the platform,the filling portion(s) (212) extending axially such that each filling portion (212) is covered by one or more preforms of aerodynamic profiles (230), - the densification by a matrix of the fibrous assembly (200) having the shape of the bladed wheel sector (300) to be obtained so as to obtain said bladed wheel sector (300) in composite material.

2. A method for manufacturing a bladed wheel sector (300) according to claim 1, wherein the manufacture of the second preform (220) of the other platform (310, 320) to be produced comprises: - the arrangement of a second fibrous platform blank in a mold having an impression, the impression comprising a main portion having the shape of the other platform to be produced and one or more grooves extending in the same direction of extension, the groove(s) comprising one or more injection ports, the second fibrous platform blank being arranged in the main portion of the impression, - the injection of a filler material through the injection port(s) so as to fill the grooves of the mold,- the heat treatment of the second fibrous platform blank and the injected filling material so as to obtain the second preform comprising (220) protruding filling portions extending along the extension direction, - the demolding of the second platform preform (220); the assembly of the second platform preform (220) with the first platform preform (210) and the airfoil preforms (230) being carried out such that each airfoil preform (230) connects one of the filling portions (212) of the first preform (210) to one of the filling portions of the second preform (220), the filling portion(s) of the second preform (220) extending axially so that each filling portion of the second preform (220) is covered by one or more airfoil preforms (230).

3. Method of manufacturing a bladed wheel sector (300) according to claim 1 or 2, wherein the first platform blank (210), and where applicable the second platform blank (220), is made by superimposing pre-impregnated plies.

4. A method for manufacturing a bladed wheel sector (300) according to any one of claims 1 to 3, wherein the cross-sectional area of ​​the grooves (512) of the mold (510) is variable along the extension direction (DE), so as to obtain portions of filling (212) presenting a cross-sectional area that varies according to the direction of extension (DE).

5. Method of manufacturing a bladed wheel sector (300) according to any one of claims 1 to 4, wherein the filling material (112) is a thermoplastic material and wherein the first fibrous platform blank (210), the aerodynamic profile preforms (230) and optionally the second fibrous platform blank (220) are impregnated with a thermoplastic resin.

6. Method of manufacturing a bladed wheel sector (300) according to any one of claims 1 to 4, wherein the filling material (112) is a thermosetting material and wherein the first fibrous platform blank (210), the aerodynamic profile preforms (230) and optionally the second fibrous platform blank (220) are impregnated with a thermosetting resin.

7. Method of manufacturing a bladed wheel sector (300) according to any one of claims 1 to 6, wherein the filling material (112) is loaded with carbon particles.

8. A method for manufacturing a bladed wheel sector (300) according to any one of claims 1 to 7, wherein the aerodynamic profile preforms (230) have a "C" shape, a pair of aerodynamic profile preforms (231, 232) placed back to back forming the fibrous reinforcement of a single aerodynamic profile (330) of the bladed wheel sector (300) to be produced, the filling portions (212) being arranged between two aerodynamic profile preforms (231, 232) belonging to the same pair.

9. A method for manufacturing a bladed wheel sector (300) according to claim 8, wherein the manufacture of the aerodynamic profile preforms (230) comprises: - the production of a fibrous aerodynamic profile blank (130) by superimposing pre-impregnated plies, - the shaping of the fibrous aerodynamic profile blank (130) by means of a vacuum membrane (602) so as to give a "C" shape to the fibrous aerodynamic profile blank (130), then

10. - the pre-consolidation of the fibrous rough aerodynamic profile (130) shaped so as to obtain the fibrous preform aerodynamic profile (230). Bladed wheel comprising a plurality of sectors (300) made according to the manufacturing process according to any one of claims 1 to 9.

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