Bladed wheel sector with filling portions

Abstract

Bladed wheel sector with filling portions The invention relates to a method for manufacturing a bladed wheel sector (300) comprising an internal platform (310), an external platform (320) and one or more aerodynamic profiles (330), comprising: - arranging a fibrous blank (111) in a mold (510) comprising one or more grooves (512), - injecting a filling material (112) so as to fill the grooves (512) of the mold (510), - heat treating the blank (111) and the injected filling material (112) so as to obtain a first platform preform (210), - assembling the first platform preform (210) with one or more aerodynamic profile preforms (230) and a second platform preform (220) in order to obtain a fibrous assembly (200), - densifying the first platform preform (210) with one or more aerodynamic profile preforms (230) and a second platform preform (220) in order to obtain a fibrous assembly (200), by a matrix of the fibrous assembly (200) so as to obtain said bladed wheel sector (300). Figure for the abstract: 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. Prior art

[0002] Stator blades are conventionally formed by an aerodynamic profile connecting an internal platform to an external platform. Stator blades are currently made of metal, particularly titanium. It is now preferable to make stator blades of composite material, and particularly organic matrix composite (OMC) material. Indeed, organic matrix composite (OMC) materials are lighter than most metals while retaining good mechanical properties. Thus, their use contributes to optimizing the performance of turbomachines or turbomachine equipment, particularly by reducing the overall mass of the turbomachine. The efficiency of the turbomachine is improved, which allows a reduction in fuel consumption and thus a reduction in harmful emissions (CO, CO2, NOx, etc.).Thus, organic matrix composite materials (OMCs) are already used for fan blades, as described in document FR 3 068 640.

[0003] However, it is difficult to obtain the optimal quantity of material at the junction between the aerodynamic profile and the platforms. Indeed, the radius between the aerodynamic profile and the platforms may lack material or have an unsatisfactory quality of material.

[0004] Furthermore, it is desirable that the junction portion between the aerodynamic profile and the platforms has an evolving section: in fact, it is preferable that the junction portion is thick in the center and thinner towards the ends of said junction portion, in order to better follow the shape of the aerodynamic profile. Statement of the invention

[0005] The aim of the invention is to propose a solution making it possible to obtain 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 inner platform, an outer platform and one or more airfoils extending radially between the two platforms, the method comprising:

[0007] - the arrangement of a first fibrous platform blank in a mold having an imprint, the imprint 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 arranged in the main portion of the imprint,

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

[0009] - the heat treatment of the first fibrous platform blank and of the filling material injected so as to obtain a first preform of one of the platforms to be produced comprising projecting filling portions extending in the direction of extension,

[0010] - the demolding of the first preform from 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 aerodynamic profile preforms 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] - 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 method makes it possible to easily obtain junctions between the aerodynamic profile and the platforms which are sufficiently filled and which have a good quality of material. The use of overmolding allows easy automation of the process and excellent repeatability. In addition, the production of the filling by overmolding allows great freedom on the shape of the filling to be produced, thus making it possible to easily obtain a variable 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 having 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] - injecting a filling material through the injection port(s) so as to fill the mold grooves,

[0017] - the heat treatment of the second platform fiber blank and of the filling material injected so as to obtain the second preform comprising projecting filling portions extending in the direction of extension,

[0018] - demolding the second platform preform;

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

[0020] According to another particular embodiment of the invention, the first platform blank, and where appropriate the second platform blank, is produced 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, the subsequent injection of a resin into the already assembled dry fiber assembly is difficult to carry out.

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

[0023] Indeed, the method 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 appropriate 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 and in which the first fibrous platform blank, the aerodynamic profile preforms and, where appropriate the second fibrous platform blank is impregnated with a thermoset 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 a suitable quantity of material and makes it possible to avoid excess or 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 fiber 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 fiber blank with an aerodynamic profile by superimposing pre-impregnated folds,

[0031] - shaping the aerodynamically profiled fiber blank by means of a membrane placed under vacuum so as to give a “C” shape to the aerodynamically profiled fiber blank, then

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

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

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

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

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

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

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

[0039] [Fig.5] [Fig.5] is a schematic 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 fiber preform of platform.

[0041] [Fig.7] [Fig.7] is a schematic sectional view of a fiber blank in profile aerodynamically shaped on a mandrel.

[0042] [Fig.8] [Fig.8] is a schematic sectional view of the assembly of the platform fiber preforms and the aerodynamic profile fiber preforms to obtain the bladed wheel sector of [Fig.l]. Description of the embodiments

[0043] [Fig.l] illustrates an example of a bladed wheel sector 300 achievable by the method of the invention. The bladed wheel sector 300 conventionally comprises an internal platform 310 and an external 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 produced by the method of the invention may comprise a single aerodynamic profile: the bladed wheel sector 300 will then be comparable to a blade provided with an internal platform and an external platform.

[0045] In the example illustrated in [Fig.l], the bladed wheel sector 300 comprises three aerodynamic profiles. However, it does not depart from the scope of the invention if the bladed wheel sector comprises a different number of aerodynamic profiles. In particular, the invention is particularly advantageous for producing bladed wheel sectors comprising between 10 and 15 sectors. The invention is also particularly advantageous for producing bladed wheel sectors corresponding to one sixth of the total bladed wheel to be produced, i.e. for bladed wheel sectors extending circumferentially over 60°.

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

[0047] The mold 510 comprises an imprint having the shape of one of the platforms to be produced. The imprint of the mold 510 comprises a main portion 511. The main portion 511 of the imprint comprises a bottom 511a. The main portion 511 of the imprint extends in depth along a depth direction DP. The main portion 511 of the imprint extends in depth to the bottom 511a along the depth direction DP. The main portion 511 of the imprint extends along a length direction DL between a first lateral edge and a second lateral edge. The main portion 511 of the imprint 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. 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 comprises grooves 512. The grooves 512 extend in the direction of extension DE. The grooves 512 are made in the bottom 511a 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, in the direction of extension DE, a first end 512a, then a central portion 512b, then a second end 512a. The grooves 512 are hollowed out in the bottom 511a of the main portion 511. The grooves 512 extend in depth in the direction of depth DP. The grooves 512 comprise 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 section along the direction of extension DE. However, preferably, the grooves 512 have a variable section along the direction of extension DE. Preferably, the area of ​​the section 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 for the grooves 512 to 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 comprises injection ports 513 opening into the 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 imprint 510 is intended to receive a fiber 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 grooves 512 as aerodynamic profiles, in other words blades, are desired on the bladed wheel sector 300 to be produced. Thus, the number of grooves conventionally corresponds to the number of aerodynamic profiles, in other words 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 imprint. The fibrous platform blank 111 rests against the bottom 511a of the main portion 511. The fibrous platform blank 111 is in contact with the bottom 511a of the main portion 511 of the imprint.

[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 fiber platform blank 111.

[0057] The platform fiber blank 111 is preferably obtained by superimposing pre-impregnated plies. It is of course not outside the scope of the invention if the platform fiber blank 111 is obtained by superimposing dry plies. It is also not outside the scope of the invention if the platform fiber 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. It is also not outside the scope of the invention if the fibers of the fiber blank are made with a mixture of material comprising at least two materials from among: carbon, glass, a ceramic.

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

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

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

[0062] The filling material 112 may be filled. For example, the filling material 112 may 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 may be filled with fibers or carbon 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 carry out a heat treatment of the injected filling material 112 and the fibrous platform blank 111.

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

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

[0067] The main body 211 of the platform fiber preform 210 extends in length and width along the extension directions DE and length DL. The main body 211 of the platform fiber 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 may extend over the entire width of the platform fiber 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 filling portions 212 extend projecting from the main body 211 in the depth direction DP. The filling portions 212 comprise a top. The tops of the filling portions 212 correspond to the parts of the filling portions 212 formed at the bottoms of the grooves 512. Thus, the filling portions 212 extend in height to the top. The filling portions 212 extend in width in the length direction DL.

[0069] The filling portions 212 may have a constant section along the direction of extension DE. However, preferably, the filling portions 212 have a variable section along the direction of extension DE, as illustrated in [Fig.6]. Preferably, the area of ​​the section 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 filling portions 212 may have a constant width along the length direction DL at the junction between the main body 211 and the filling portions 212 along the extension direction DE. The tops of the filling portions 212 may have a variable width along the length direction DL along the extension direction DE. In particular, it is preferable for the filling portions 212 to be less wide at the ends 212a of said filling portions 212 than in the central portion 212b of said filling portions 212 along the extension direction DE.

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

[0073] The platform fiber preform 210 can be used to produce the internal platform or the external platform of the bladed wheel sector to be produced. It thus constitutes the first platform fiber preform 210, obtained from a first platform fiber blank 111. The platform fiber preform 220 of the other platform can be produced in a similar manner to that described previously, from a second platform fiber blank. It constitutes the second platform fiber preform 220. Thus, the two platform fiber preforms 210 and 220 can be produced according to the method described previously. For the remainder of the description, it will be considered that the first platform fiber preform platform 210 is intended to form the internal platform of the bladed wheel sector to be obtained and that the second platform fiber preform 220 is intended to form the external platform of the bladed wheel sector to be obtained.

[0074] In particular, the two platform fiber preforms 210 and 220 are made of the same material. The two platform fiber preforms 210 and 220 are made with fibers of the same nature and the same size. The two platform fiber 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 conventionally different between the junction with the external platform and the junction with the internal 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 internal platform, may be thicker than the main body of the second platform fiber preform 220, intended to form the external platform. In the case where the first platform fiber blank 111 and the second platform fiber blank are produced by superimposing plies, the number of plies of the first fiber blank may be different from that of the second fiber blank.For example, the second platform fiber blank may comprise a number of plies between 40% and 60% of the number of plies of the first platform fiber blank 111. For example, the second platform fiber blank may comprise 6 plies and the first platform fiber blank 111 may comprise 12 plies.

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

[0078] The aerodynamic profile fiber blank 130 is preferably obtained by superimposing pre-impregnated plies. It is of course not beyond the scope of the invention if the aerodynamic profile fiber blank 130 is obtained by superimposing dry plies. It is also not beyond the scope of the invention if the aerodynamic profile fiber blank 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 same nature and of the same dimension as the two platform fiber preforms 210 and 220. The aerodynamic profile fiber blanks 130 are made with the same resin as the platform fiber blanks 111.

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

[0081] As illustrated in [Fig.7], the aerodynamically shaped fiber blank 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 aerodynamically shaped fiber blank 130 are bent on the same side, so as to obtain a “C” shape.

[0082] The shaping of the aerodynamic profile fiber blank 130 into an aerodynamic profile fiber preform 230 can be facilitated by the use of a tarpaulin 602. In particular, the tarpaulin 602 can be placed under vacuum to facilitate the shaping of the aerodynamic profile fiber blank 130. This fiber preform being heated prior to vacuum drawing in order to lower its viscosity and facilitate forming. The heating can be carried out using infrared radiation or any other heating means.

[0083] The shaped aerodynamic profile fiber blank 130 is then preconsolidated to obtain the aerodynamic profile fiber preform 230. The preconsolidation is conventionally carried out by heat treatment. In the case of a preform with a thermosetting matrix, the matrix remains with a very low rate of advancement after the shaping step, in order to keep all of its development at low viscosity during the assembly step.

[0084] A fiber preform of aerodynamic profile 230 is thus obtained 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 a “C”.

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

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

[0087] The platform fiber preforms 210 and 220 are oriented so that the extension direction DE corresponds to the axial direction DA of the bladed wheel sector 300 to be produced. Similarly, the platform fiber preforms 210 and 220 are oriented so 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 profile fiber preforms 230 are assembled in pairs to form the aerodynamic profiles. Each pair of aerodynamic profile fiber preforms 230 comprises a first aerodynamic profile fiber preform 231 and a second aerodynamic profile fiber preform 232. Each first aerodynamic profile fiber preform 231 is thus positioned with its back to the second aerodynamic profile fiber preform 232 belonging to the same pair. The central portion 230b of each first aerodynamic profile fiber preform 231 is thus in contact with the central portion 230b of the second aerodynamic profile fiber preform 232 belonging to the same pair.The end portions 230a of the first aerodynamic profile fiber preforms 231 are all oriented in the same first direction relative to the circumferential direction Dc and the end portions 230a of the second aerodynamic profile fiber 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 two legs extend and from the lower end of which two other legs extend, each leg being formed by an end portion 230a. The pairs of aerodynamic profile fiber preforms 230 are arranged so that one of the filling portions 212 of the first platform fiber preform 210 is present between two legs at the upper end of the “H” and one of the filling portions of the second platform fiber preform 220 is present 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 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 disposed 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 fiber preforms 230.

[0092] The fibrous assembly 200 thus obtained is then subjected to a heat treatment so as to crosslink or consolidate the matrix. If the fibrous assembly 200 is formed by 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 by 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 porosities of the fibrous assembly 200, a bladed wheel sector 300 is obtained as illustrated in [Fig.l]. The bladed wheel sector 300 is intended to be assembled with other bladed wheel sectors so as to obtain a complete bladed wheel. Such a bladed wheel is intended to be installed in an aircraft turbomachine.

Claims

Claims

1. A method of manufacturing a bladed wheel sector (300) made of an organic matrix composite material, said sector (300) comprising an internal platform (310), an external platform (320) and one or more aerodynamic profiles (330) extending radially between the two platforms (310, 320), the method comprising: - arranging a first fibrous platform blank (111) in a mold (510) having an imprint, the imprint 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 in the same direction of extension (DE), the groove(s) (512) comprising one or more injection ports (513), the first fibrous platform blank (111) being arranged in the main portion (511) of the imprint, - injecting of 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 fibrous platform blank (111) and the injected filling material (112) so as to obtain a first preform (210) of one of the platforms (310, 320) to be produced comprising projecting filling portions (212) extending in the direction of extension (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 platform preform (210) and the second platform preform (220),the filling portion(s) (212) extending axially such that each filling portion (212) is covered by one or more aerodynamic profile preforms (230), - 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 of manufacturing a bladed wheel sector (300) according to claim 1, wherein the manufacturing of the second preform (220) of the other platform (310, 320) to be produced comprises: - arranging a second fibrous platform blank in a mold having 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 injection ports, the second fibrous platform blank being arranged in the main portion of the imprint, - injecting a filling material through the injection port(s) so as to fill the grooves of the mold,- heat treatment of the second platform fiber blank and the injected filling material so as to obtain the second preform comprising (220) projecting filling portions extending in the direction of extension, - demolding the second platform preform (220); assembling the second platform preform (220) with the first platform preform (210) and the aerodynamic profile preforms (230) being carried out so that each aerodynamic profile 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 aerodynamic profile preforms (230).,

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

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

5. A 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, where appropriate, the second fibrous platform blank (220) are impregnated with a thermoplastic resin.

6. A 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, where appropriate, the second fibrous platform blank (220) are impregnated with a thermosetting resin.

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

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

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

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