Blade of composite material for an aircraft turbine engine

Abstract

The present invention relates to a blade of composite material, comprising: - a 3D woven fibrous reinforcement (100f) comprising an airfoil portion (102f) extending in a radial direction and at least one platform portion (105f) extending from a radial end of the airfoil portion, the at least one platform portion comprising a disconnection defining a housing (106) extending in an axial direction (A) and opening onto at least one of the axial ends (100fa) of the reinforcement, - at least one metal mounting insert (200), each mounting insert comprising at least one connection portion (202) located in a corresponding housing and secured to the reinforcement, and a mounting portion (204) located outside the reinforcement and configured to attach the blade to a shroud, and - an organic matrix densifying the fibrous reinforcement.

Description

Description Title of the invention: Composite material blade for an aircraft turbomachine Technical Field

[0001] This paper concerns a composite material blade for an aircraft turbomachine, specifically a flow straightening blade for a secondary annular duct of a turbofan aircraft turbomachine. This paper also covers a bladed assembly and an associated manufacturing process. Previous technique

[0002] The use of composite materials allows for lighter turbomachine blades compared to those made of metal. Their use helps optimize turbomachine performance, particularly by reducing the overall mass of the turbomachine, thereby lowering fuel consumption, which in turn leads to a reduction in harmful emissions (CO, CO2, NO). X ...).

[0003] Secondary flux rectifiers are large parts; manufacturing them from composite material allows for significant weight reduction.

[0004] Secondary flow straighteners can be subjected to significant stress during operation. The stresses on metallic flow straighteners can be particularly high in the area where they connect to the shell. To reduce mass, a flow straightener with a composite blade and a metallic platform can be considered. Current assembly solutions require the use of mechanical fasteners such as screws and nuts. These screws must not protrude into the flow channel, as this could disrupt the flow and affect aerodynamic performance. Non-structural platforms are then added on top to reconstitute the flow channel. A specific drawback of these solutions is the shear stress placed on the screws to secure the blade, which may not be compatible with the loads required for certain applications.We also know of CN 110402320 which describes a turbomachine blade and an associated manufacturing method, CA2848018 which describes a manufacturing process for a turbine distributor sector or compressor rectifier in composite material and CA2891289 which describes a preform and module of one-piece blades for an intermediate turbomachine casing.

[0005] It is therefore desirable to have blades with a controlled mass that maintain high mechanical properties in the interface area of ​​the part, typically the interface with the ferrule, and allow the platform to be fixed with little or no impact on the aerodynamic flow. Description of the invention

[0006] This presentation concerns a composite material blade for an aircraft turbomachine, comprising: - a three-dimensionally woven fibrous reinforcement comprising a blade portion extending in a radial direction and at least one platform portion extending from a radial end of the blade portion and transverse thereto, said at least one platform portion comprising a detachment defining a housing extending in an axial direction and opening onto at least one of the axial ends of the reinforcement, - at least one metallic mounting insert, each mounting insert comprising at least one connecting portion located in a corresponding housing and integral with the reinforcement, and a mounting portion located outside the reinforcement and configured to secure the blade to a ferrule, and - an organic matrix that densifies the fibrous reinforcement.

[0007] The use of a composite material makes it possible to control the mass of the blade and the fact of housing each connecting part in a housing made in the platform makes it possible to reduce, or even eliminate, the use of mechanical fixing solutions such as screw-nut, thus reducing the impact on the aerodynamic duct, while maintaining high mechanical properties in the interface area.

[0008] In some embodiments, the blade part includes a portion of the aerodynamic profile comprising, at the radial end, a decoupling separating a first part of the platform, located on the lower surface, from a second part of the platform located on the upper surface.

[0009] Such a feature, presenting a platform opening on both the upper and lower surfaces, further improves mechanical performance and facilitates integration.

[0010] In some embodiments, the blade is a multiplet blade, the blade portion comprising at least two aerodynamic profile portions connected by each platform portion.

[0011] The invention applies to the case of a multiplet blade, for example doublet, or alternatively to a simplet blade which defines a single aerodynamic profile.

[0012] In some embodiments, each connecting part has undulations along at least one direction transverse to the axial direction, and the fibrous reinforcement defines internal reliefs cooperating with these undulations.

[0013] This characteristic ensures better transfer of forces between the mounting insert(s) and the fibrous reinforcement.

[0014] In some embodiments, each connecting element and its corresponding housing extend from one axial end of the reinforcement to an opposite axial end. This feature allows for upstream and downstream interfaces to be created with a continuous connecting element along the entire axial dimension of the platform. This solution is more mechanically efficient but may increase mass. Generally, the preferred solution between mechanical efficiency and mass depends on the intended application.

[0015] In some embodiments, each mounting insert comprises two connecting parts linked by the mounting part, each connecting part being inserted into a housing of a separate platform part.

[0016] Such a feature, corresponding to the use of a continuous insert between the intrados and extrados, provides a mechanical gain as well as a benefit in terms of geometric precision but can penalize the mass.

[0017] In some embodiments, the fibrous reinforcement is formed of carbon fibers, glass fibers, aramid fibers, or a mixture of such fibers.

[0018] In some embodiments, the blade is a straightening blade for an airflow secondary annular duct of a turbofan aircraft turbomachine.

[0019] The present presentation also relates to a bladed assembly intended to be mounted on an aircraft, comprising an inner ferrule and an outer ferrule delimiting an airflow channel and a plurality of blades as described above fixed to said ferrules and extending between them.

[0020] This presentation also relates to an aircraft turbomachine comprising a bladed assembly as described above.

[0021] This presentation also concerns a manufacturing process for a blade as described above, comprising: - obtaining an assembly comprising the fibrous reinforcement, shaped to the desired blade shape, and each connecting part introduced into the corresponding housing, and - the densification of the fibrous reinforcement by the organic matrix comprising an introduction of the resin into a porosity of the fibrous reinforcement of the assembly.

[0022] In some embodiments, each connecting part is integral with a precursor of the mounting part located outside the reinforcement, and, after the densification of the fibrous reinforcement by the organic matrix, the mounting part is obtained by machining the precursor, or by linking to the latter a third element.

[0023] Such a feature makes it possible to simplify sealing in forming tooling, or to improve the accuracy of the interfaces of the part with regard to the aerodynamic profile.

[0024] In some embodiments, the resin is introduced by resin transfer molding technique.

[0025] The aforementioned features and advantages, as well as others, will become apparent upon reading the detailed description that follows, which refers to the attached drawings. Brief description of the drawings

[0026] The attached drawings are schematic and primarily intended to illustrate the principles of the presentation. In these drawings, identical elements (or parts of elements) are identified by the same reference symbols from one figure to another. [Fig. 1] Figure 1 is a schematic cross-sectional view of a turbofan engine that can be implemented within the framework of the invention. [Fig. 2] Figure 2 represents a succession of steps of an example of a manufacturing process for a blade according to the invention. [Fig. 3] Figure 3 represents, schematically and partially, an example of a fibrous blank intended to form the fibrous reinforcement of a blade according to the invention. [Fig. 4] Figure 4 represents, schematically and partially, the fibrous reinforcement of the blade to be obtained, formed after shaping the rough shape of Figure 3. [Fig. 5] Figure 5 schematically and partially represents the fibrous reinforcement of Figure 4 after insertion of a mounting insert into the platform parts. [Fig. 6] Figure 6 represents, schematically and in isolation, a variant of a mounting insert. [Fig. 7] Figure 7 represents, schematically and in isolation, another variant of mounting insert. [Fig. 8] Figure 8 schematically and partially represents a fibrous reinforcement defining internal reliefs cooperating with the undulations of the mounting insert of Figure 7. [Fig. 9] Figure 9 schematically and partially represents another example of a fibrous blank intended to form the fibrous reinforcement of a blade according to the invention. [Fig. 10] Figure 10 represents, schematically and partially, the fibrous reinforcement, obtained after shaping the blank of figure 9, and after inserting a metallic mounting insert. [Fig. 11] Figure 11 represents, schematically and in isolation, a variant of a metal mounting insert. [Fig. 12] Figure 12 represents, schematically and partially, a variant of fibrous reinforcement of a doublet blade according to the invention. Description of the implementation methods

[0027] Figure 1 shows, in cross-section along a vertical plane passing through its principal axis A, a turbofan engine 1 as described above. It comprises, from upstream to downstream along the airflow path, a fan 2, a low-pressure compressor 3, a high-pressure compressor 4, a combustion chamber 5, a high-pressure turbine 6, and a low-pressure turbine 7.

[0028] The blower 2 allows the aspiration of an airflow to which two independent circulations are imposed, to form a primary airflow (represented by the arrow FP in figure 1 and corresponding to the hot flow) and a secondary airflow (represented by the arrow FS in figure 1 and corresponding to the cold flow).

[0029] The air from the primary flow FP can for example be compressed within the low pressure compressor 3 and then the high pressure compressor 4, and then mixed with a fuel and burned within a combustion chamber 5. The gases expelled from the combustion chamber 5 can pass through a high pressure turbine 6 and then a low pressure turbine 7 before undergoing acceleration through a nozzle.

[0030] Compressors 3, 4 and turbines 5, 6 comprise several stages of fixed blades (called "stators") and moving blades (called "rotors"). The moving blades consist of a ring of vanes mounted radially on a disk, which drives a rotating shaft under the effect of a passing air or gas flow. Each blade has a blade attached to a foot that is fitted into a groove in the disk to hold the blade in place during the operation of the turbomachine. The fixed blades, generally located between each stage of moving blades, straighten the airflow before it enters the next stage of moving blades.

[0031] The secondary flow FS bypasses the hot part of the reactor. The secondary flow FS channel is delimited by an inner (radially internal) ferrule 8 and an outer (radially external) ferrule 9, and includes a straightener equipped with outlet guide vanes 10 (or "OGV" for "Outlet Guide Vane") arranged downstream of the fan 2. The vanes 10 have the particular function of straightening the cold flow exiting the fan 2 to obtain the maximum thrust. These blades 10 also have a structural function and must in particular be able to withstand forces exerted by the engine in operation (for example in tangential bending, also called "fan twist"), or a shock due to the ingestion of an object by the blower 2, or even the detachment of a blade from the blower 2. The blades 10 extend between the ferrule 8 and the ferrule 9. The blades 10 extend in a radial direction R.The presentation is illustrated in connection with a 10 OGV blade but it remains applicable to any type of rectifier, more particularly to structural flow rectifiers for example to structural guide vanes (or "SGV" for "Structural Guide Vane"), or more generally to organic matrix composite material blades intended to be fixed to a ferrule using at least one metallic mounting part.

[0032] In this presentation, the terms "axial", "radial", "tangential" and their derivatives are defined with respect to the main axis of the turbomachine; the terms "upstream" and "downstream" are defined with respect to the airflow in the turbomachine.

[0033] Figure 2 illustrates a sequence of steps in a process for manufacturing an example of a blade 10 according to the invention.

[0034] A fibrous blank intended to form a fibrous reinforcement for the blade to be obtained is first produced by three-dimensional weaving (step E10). "Three-dimensional weaving" or "3D weaving" refers here to a weaving method in which at least some of the warp yarns interlock with weft yarns across several weft layers. It should be noted that a reversal of roles between warp and weft is possible and should be considered as also covered by the claims. In particular, an "interlock" weave can be used to form the blank. An "interlock" weave is a three-dimensional weave in which each layer of weft yarns interlocks several layers of warp yarns with all the yarns in the same weft column having the same movement within the plane of the weave.The creation of the fibrous blank through 3D weaving allows for bonding between the layers, thus ensuring good mechanical strength of both the blank and the resulting composite part, all in a single textile operation. 3D weaving is performed on a Jacquard loom using a well-established process.

[0035] Figure 3 shows an example of a fibrous blank 100 that can be implemented within the scope of the invention. The blank 100, as well as the fibrous reinforcement lOOf obtained after shaping it, can be formed into a single piece of three-dimensional fabric. The blank 100 includes a blade portion 102 which is intended here to form a single airfoil section after shaping (in the case of a simple blade). However, the invention is not limited to this embodiment, as will be described later with reference to Figure 12.

[0036] The blank 100, as well as the fibrous reinforcement lOOf obtained after its shaping, can be made of carbon fibers, glass fibers, aramid fibers, or a mixture of such fibers. In the case of carbon fibers, one can use fibers marketed under the reference HexTow® IM7, IM10, or AS4 by Hexcel, or under the reference Tl 100 by Toray.

[0037] Part 102 is obtained by three-dimensional weaving and, in the illustrated example, has at each of its radial ends 102r, a debonding DR separating part 102 into two unbound fibrous portions 105, 109 defining a fibrous reinforcement of the blade platforms to be obtained. Portions 105, 109 are each obtained by three-dimensional weaving. Portions 105 and 109 are woven together only along part 102. Portions 105 and 109 can be separated from each other on either side of the R direction. Portions 105 and 109 are in the textile continuity of part 102. In the illustrated example, blank 100 has an internal radial DR debonding and an external radial DR debonding, but the invention remains within the scope of this approach when there is only one radial debonding, at either the internal or external radial end. Unless otherwise specified, the terms "internal" and "external" are used with respect to the radial direction R.In a way known in itself, a debinding is made between two layers of warp yarns by not passing weft yarns through the debinding zone so as not to bind yarns of warp layers located on either side of the debinding.

[0038] Figures 3 to 5, which will now be described, illustrate a possible positioning of mounting inserts in recesses provided in the platform sections. In the illustrated embodiment, the recesses and inserts are shown only on internal platform sections, but those skilled in the art will recognize that the invention is not limited to this scenario, as the inserts and recesses can also be located on external platform sections, or only on these. It will also be recognized that the recesses and inserts can, in addition, or alternatively, be present on the upstream axial end of the blade, and not only on its downstream axial end as illustrated. Each platform section can be provided with at least one recess, but the invention remains within the scope of the invention if the recess(es) are not present on all platform sections.

[0039] The blank 100 is shaped to form the desired fibrous reinforcement lOOf of the blade, by giving part 102 the desired aerodynamic profile shape to obtain the blade portion 102f of the reinforcement lOOf, and by deploying portions 105 and 109 in the directions indicated by arrows D in Figure 3 (step E20). The shaping of the blank corresponds to a well-known technique. In the example considered here, on each radial end 102fr of the blade portion 102f, a first platform portion 105f is obtained on the lower surface, and a second platform portion 105f on the upper surface, each of the first and second platform portions being transverse to the portion 102f, for example, substantially perpendicular to it.

[0040] In addition to the DR unties, each portion 105f may include a DA untie, made in direction A, so as to define two untied portions 104f, 109f which can be separated on either side of direction A and defining between them an internal recess 106. Each DA untie may be bounded, in the tangential direction T, by two edges B1 and B2 beyond which the portions 104f, 109f are woven together. The recess 106 extends along direction A and here opens onto the downstream axial end lOOfa of the reinforcement lOOf. The recess 106 may correspond to an internal pocket defined in each portion 105f. The housing 106 can extend, along the direction A, between an opening 1061 leading to the end lOOfa and a bottom 1063 delimiting the corresponding debonding and beyond which the portions 104f, 109f are woven together.Generally, the width L106 of the unit 106 can occupy at least 50%, for example at least 75%, of the width L105f of the corresponding section 105f. The fraction of the width L105f occupied by the unit 106 can be between 50% and 95%, for example between 75% and 95%. Unless otherwise specified, these widths are measured along the direction T.

[0041] A metallic mounting insert 200 can then be inserted into each housing 106 (step E30). Each insert 200 comprises a connecting portion 202 located in a corresponding housing 106 and inserted through the opening 1061, and a mounting portion 204 located outside the reinforcement lOOf and configured to secure the blade to a ferrule. The portion 204 may, for example, have a conical bearing surface, but those skilled in the art will recognize that the invention remains applicable regardless of the method of securing the blade to the ferrule.

[0042] The insert 200 can be manufactured using a known technique, such as casting, forging, machining, or additive manufacturing. The insert 200 can be made of steel, titanium or titanium alloy, aluminum, or aluminum alloy. The insert 200 may undergo a surface treatment prior to use. This treatment may include sandblasting, grinding, degreasing, pickling, or a combination of known treatments. A primer may be applied after this initial treatment. A film of adhesive or paste adhesive may be applied to the insert 200 before insertion into the reinforcement, ideally just before introducing the resin to form the matrix. Alternatively, this application is omitted, and the insert is bonded to the reinforcement solely by the organic matrix.

[0043] In the illustrated example, a separate insert 200 is introduced into each housing 106, but the invention is not limited to this embodiment, as will be described below. Generally, the portion 202 can extend over more than 20 mm. The portion 202 can extend over more than 10% of the axial dimension D106 of the corresponding housing 106. The width L202 of the portion 202 can correspond to the width L106 of the corresponding housing 106 to within 10%. Generally, the thickness of each portion 105f into which the insert 200 is introduced, measured along the direction R, can be less than or equal to 10 mm, for example, between 5 mm and 10 mm.

[0044] Part 202 is transverse, for example perpendicular, to part 204. In the illustrated example, part 202 is integral (a single piece) with part 204. The insert 200 may include an intermediate, curved portion 203 (forming an elbow here) connecting part 202 to part 204. Part 202 may extend parallel to direction A, or possibly at a slight non-zero angle to it. Part 202 is not, in particular, parallel to direction R. A solution outside the invention where the insert has radial, rather than axial, connecting portions introduced into the profile portion, i.e., into a thin area, would limit the possibilities for improving load transfer compared to introducing the insert into the platform portion as in the invention.

[0045] The process then continues with the densification of the fibrous reinforcement by the organic matrix (step E40). The organic matrix is ​​obtained using established techniques, such as resin transfer molding. According to this method, the lOOf reinforcement is placed in a mold with the external shape of the part to be produced. A thermosetting or thermoplastic resin is injected into the internal space of the mold containing the lOOf reinforcement. A pressure gradient can be established in this internal space between the resin injection point and the drainage holes to control and optimize the impregnation of the lOOf reinforcement by the resin. In the case of a thermosetting resin, a curing step can then be performed to obtain the matrix through resin cross-linking. In the case of a thermoplastic resin, the matrix is ​​obtained by cooling the introduced resin.For example, the resin may be an epoxy resin, for example marketed under the reference CYCOM® PR 520 by the company Syensqo, or HexFlow® RTM230 or RTM250 by the company Hexcel.

[0046] The blade is then removed from the mold, deburred, and possibly machined. A metal shim can optionally be attached to the leading edge of the blade, for example by gluing, or alternatively, the shim can be molded along with the blade.

[0047] We have just described an example where the insert 200 is already in its final geometry (designed to allow attachment to the ferrule) at the time of its insertion into the housing 106. However, the invention is not limited to this scenario, since only a precursor of the mounting portion may be present at the time of die formation, and the mounting portion can then be obtained from this precursor once the organic matrix has been formed (step E50). In this case, the connecting portion is introduced into the housing and is integral with the precursor, which protrudes from the reinforcement during die formation. Following the formation of the organic matrix, the precursor can be machined to the shape of the mounting portion, or connected to a third element to form the mounting portion.

[0048] In the example shown in Figure 5, part 202 is generally flat, without any relief on its faces or edges. However, this does not depart from the scope of the invention when the opposite is true, as illustrated in particular by Figures 6 and 7, which will now be described.

[0049] The mounting insert 210 of Figure 6 comprises a mounting portion 214 and a connecting portion 212. The portion 212 has undulations along the direction R. The insert 210 comprises two opposing faces 213, each transverse to the direction R, and two opposing edges 215, each connecting the faces 213. Each face 213 of the insert 210 is not planar and has an alternating pattern of raised ridges 213a and recessed ridges 213b. The ridges 213a, or undulations, may or may not be regularly spaced along the direction A. The ridges 213a, or undulations, may or may not have the same shape. The reliefs 213a, 213b result here in a variation of the height of each face 213, this height being measured with respect to the direction R. In the example of figure 6, the thickness e212 of the part 212 is variable along the direction A.Unless otherwise specified, the thickness e212 corresponds to the distance between opposite faces 213 measured along direction R. The ratio between the thickness e212 measured on a relief 213a and the thickness e212 measured on a relief 213b can be greater than or equal to 1.1, for example, between 1.1 and 1.6, or greater than or equal to 1.6. Such values ​​for this ratio further improve force transfer due to the complementary nature of the shapes. For example, the thickness e212 measured on a relief 213b can be less than or equal to 2 mm, for example, between 0.5 mm and 2 mm. The thickness e212 measured on a relief 213a can be greater than or equal to 4 mm, for example, 5 mm. Generally speaking, the thickness of the insert (whatever its shape) can be between 1 mm and 6 mm, for example between 4 mm and 5 mm.

[0050] The mounting insert 220 of Figure 7 comprises a mounting portion 224 and a connecting portion 222. As in Figure 6, each face 223 of the insert 220 is not flat and features alternating raised and recessed reliefs 223a and 223b. While the reliefs 213a and 213b result in a variation in the height of each face 223 as previously described, there is, however, no significant variation in the thickness e222 of the portion 222 along direction A in the case of Figure 7. Those skilled in the art will recognize that other shapes than those illustrated can be considered for the undulations.

[0051] Figure 8 illustrates the insert 220 introduced into the platform portion 115f, which defines reliefs 114f that cooperate with these undulations. Thus, the reliefs 114f, which correspond to woven portions, fill the hollow reliefs 223b. In the illustrated case, the separation defining the housing was created with a variable height along the R direction. The face 116f of each portion 115f intended to be located on the grain side advantageously does not have any local excess thickness, avoiding any risk of disrupting the airflow and, in particular, making the use of an added piece to make the platform aerodynamic superfluous.

[0052] We have just described the case of undulations of the bonding part along the R direction, but it should be noted that there can also be undulations along the T direction, or only undulations along the T direction. Tangential undulations allow us to limit the required thickness.

[0053] The examples just described concern an extension of the mounting insert's connecting portion limited along the axial dimension of the corresponding platform portion. However, the invention is not limited to this case, as illustrated in Figures 9 to 11, which will now be described.

[0054] Figure 9 shows a three-dimensional weaving blank 120 comprising a blade portion 122 and a radial DR debond on at least one radial end 122r of the portion 122. The DR debond separates the portion 122 into two unbound fibrous sections 125 defining a fibrous reinforcement of the blade platforms to be obtained. Unlike what was described above, the housing 126 extends over the entire axial dimension of the corresponding portion 125.

[0055] The fibrous reinforcement 120f obtained after shaping the blank 120 comprises a blade portion 122f and two platform portions 125f (see Figure 10). The housing 126 extends along direction A and terminates here at the two axial ends 120fa, 120fb of the reinforcement 100f. The metallic mounting insert 230 comprises a connecting portion 232 located in the housing 126 and also extending from one end 120fa to another 120fb, as well as a mounting portion 234.

[0056] Figure 11 illustrates a variant of the mounting insert 240, which comprises a mounting portion 244 from which extend two connecting portions 242, each intended to be inserted into a recess in a corresponding platform portion. Thus, one portion 242 is inserted into the recess of the platform portion on the lower surface (intrados), and the other portion 242 is inserted into the recess of the platform portion on the upper surface (extrados). This variant is applicable to both through-holes, as illustrated in Figures 9 and 10, and blind-holes, as described previously. The insert 240 in Figure 11 provides downstream continuity, but continuity is naturally not departed from the scope of the invention if it is also provided upstream.

[0057] Figure 12 illustrates a reinforcement 130f of a doublet blade that defines two airfoil sections 132f and two platform sections 135f, each equipped with a housing opening through an aperture 1361 for receiving a mounting insert, similarly to what was described above. Other variations are possible compared to the illustrated embodiments; for example, the platform could be formed on only one side, either the lower or upper surface, by simply folding the preform (without separating the blade to form the platform) with an insert inserted within it.

[0058] Although the present invention has been described with reference to specific embodiments, those skilled in the art will recognize that modifications and changes can be made to these examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the various embodiments illustrated / mentioned can be combined in additional embodiments. Therefore, the description and drawings should be considered in an illustrative rather than restrictive sense.

[0059] The expression "between ... and ..." should be understood as including the boundaries.

Claims

Demands

1. Blade (10) made of composite material for an aircraft turbomachine, comprising: - a three-dimensionally woven fibrous reinforcement (100f; 120f; 130f) comprising a blade portion (102f; 122f; 132f) extending in a radial direction (R) and at least one platform portion (105f; 115f; 125f; 135f) extending from a radial end (102r; 122r) of the blade portion and transverse thereto, said at least one platform portion comprising a debond (DA) defining a housing (106; 126) extending in an axial direction (A) and opening onto at least one of the axial ends (100fa; 120fa; 120fb) of the reinforcement, - at least one metallic mounting insert (200; 210; 220; 230; 240), each mounting insert comprising at least one connecting portion (202; 212; 222; 232; 242) located in a corresponding housing and integral with the reinforcement, and a mounting portion (204; 214; 224; 234; 244) located outside the reinforcement and configured to secure the blade to a ferrule (8; 9), and - an organic matrix that densifies the fibrous reinforcement.

2. Blade (10) according to claim 1, wherein the (102f; 122f) portion of the blade comprises a portion of the airfoil comprising, at the radial end (102r; 122r), a decoupling (DR) separating a first (105f; 115f; 125f) portion of the platform, located on the lower surface, from a second (105f; 115f; 125f) portion of the platform located on the upper surface.

3. Blade according to claim 1 or 2, wherein the blade is a multiplet blade, the blade portion comprising at least two airfoil portions (132f) connected by each platform portion (135f).

4. Blade (10) according to any one of claims 1 to 3, wherein each connecting part (212; 222) has undulations (213a; 213b; 223a; 223b) along at least one direction (R) transverse to the axial direction (A), and wherein the fibrous reinforcement defines internal reliefs (114f) cooperating with these undulations.

5. Blade (10) according to any one of claims 1 to 4, wherein each connecting part (232) and the corresponding housing extend from an axial end (120fa) of the reinforcement (120f) to an opposite axial end (120fb).

6. Blade (10) according to claim 2 or according to any one of claims 3 to 5 related to claim 2, wherein each mounting insert (240) comprises two connecting parts (242) linked by the mounting part (244), each connecting part being inserted into a housing of a separate platform part.

7. Blade (10) according to any one of claims 1 to 6, wherein the fibrous reinforcement (100f; 120f; 130f) is formed of carbon fibers, glass fibers, aramid fibers, or a mixture of such fibers.

8. Blade (10) according to any one of claims 1 to 7, wherein the blade is an airflow straightening blade for a secondary annular duct of a turbofan aircraft turbomachine.

9. A bladed assembly intended to be mounted on an aircraft, comprising an inner ferrule (8) and an outer ferrule (9) delimiting an airflow channel and a plurality of blades (10) according to any one of claims 1 to 8 attached to said ferrules and extending between them.

10. Aircraft turbomachine comprising a bladed assembly according to claim 9.

11. A method for manufacturing a blade according to any one of claims 1 to 8, comprising: - obtaining (E30) an assembly comprising the fibrous reinforcement, shaped to the blade to be obtained, and each connecting part inserted into the corresponding housing, and - densification (E40) of the fibrous reinforcement by the organic matrix comprising an introduction of the resin into a porosity of the fibrous reinforcement of the assembly.

12. A method according to claim 11, wherein each connecting part is integral with a precursor of the mounting part located outside the reinforcement, and wherein, after densification (E40) of the fibrous reinforcement by the organic matrix, the mounting part is obtained (E50) by machining the precursor, or by bonding to the latter a third element.

13. A method according to claim 11 or 12, wherein the resin is introduced by resin transfer molding technique.

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