One-piece vane preform comprising a unidirectional fabric through portion

Abstract

The present disclosure relates to a blade fiber preform (200) for a turbomachine having a three-dimensional or multi-layer weave integrally comprising a root preform portion (230), a shank preform portion (250), a blade preform portion (220), at least one lower platform preform portion (240) and at least one upper platform preform portion (260), the preform further comprising an upstream wall preform portion (270) and a downstream wall preform portion (280) formed from first to fourth unidirectional fabric portions (107, 108, 109, 110).

Description

Technical Field

[0001] This invention relates to the field of blades made of composite materials, including fiber reinforcements densified by a matrix, with the target field being gas turbine blades for aero engines or industrial turbines. Background Technology

[0002] Proposals have been made to produce composite blades for turbines.

[0003] Organic matrix composites (CMOs) and ceramic matrix composites (CMCs) have replaced metal components in certain parts of turbines. Their use helps optimize aircraft performance, particularly by significantly reducing harmful emissions (such as CO, CO2, NOx, etc.) by improving turbine efficiency and reducing overall turbine weight.

[0004] US Document No. 9,086,454 describes a method for manufacturing turbine blades made of composite materials, including fiber reinforcements densified by a matrix. More specifically, the method is characterized by forming a fiber preform produced by three-dimensional weaving to obtain a monolithic fiber preform having a first portion forming blade airfoils and a root preform, and at least one second portion forming a blade platform preform. Thus, after densification of the preform, a blade made of composite material can be obtained, having fiber reinforcements formed by the preform and densified by a matrix, the blade being integrally structured with a platform provided with overlapping spoilers. The monolithic production of fiber reinforcements by three-dimensional weaving offers several advantages, such as imparting excellent mechanical properties to the blade (especially good anti-delamination properties) and allowing the production of components with complex geometries.

[0005] Gas turbine blades require secondary sealing and aerodynamic functions. These functions are achieved at the lower part of the blade (near the blade root) by a platform connected by walls. In the case of blades made of composite materials with fiber reinforcements produced in a single 3D braided fabric, the unfolding of the walls and platforms during the forming of the fiber preform (production of the blade preform) can be difficult due to the limitations imposed by the unfolding of the 3D braided texture and the tri-point problem at the intersection of the walls and the blade root.

[0006] Another challenge lies in cutting the fiber preform. In addition to trimming, some localized, non-through cuts are required. Currently, these cuts are done mechanically, which causes significant stress / deformation in the woven fabric. Furthermore, because the cutting is done manually, the precision is low (1 to 2 millimeters), and the outline is not very regular. Summary of the Invention

[0007] Therefore, it is desirable to propose a solution for producing blades made of composite materials through three-dimensional weaving that does not have the aforementioned drawbacks.

[0008] Therefore, the present invention proposes a method for manufacturing fiber preforms of turbine blades made of composite materials, the method comprising:

[0009] - A fiber preform is formed by three-dimensional or multi-layered weaving between multiple warp and weft yarns, wherein the multiple warp yarns extend in a longitudinal direction corresponding to the longitudinal direction of the blade to be produced, and the multiple weft yarns extend in a transverse direction corresponding to the transverse direction of the blade to be produced.

[0010] The fiber preform includes:

[0011] - A first set of warp and weft layers, which are combined together, the first set extending longitudinally between a first longitudinal end and a second longitudinal end, extending transversely between a first transverse end and a second transverse end respectively used to form the leading and trailing edges of the blade, and extending along the thickness direction of the blank between a first surface and a second surface respectively used to form the pressure surface and the suction surface of the blade, the first set forming a first portion of the blank, the first portion corresponding to at least a portion of the blade airfoil;

[0012] - A second set of warp and weft layers, which are at least partially bonded together to form a second portion of the blank, the second portion corresponding to at least a portion of the blade under-platform preform;

[0013] - A third set of warp and weft layers, which are at least partially bonded together to form a third portion of the preform, the third portion corresponding to at least a portion of the platform preform on the blade.

[0014] The yarn in the first part is not combined with the yarn in the second and third parts.

[0015] The fiber preform further includes, on the first surface of the first portion, a first unidirectional fabric portion and a second unidirectional fabric portion, respectively located near the first transverse end and the second transverse end of the first portion; and on one side of the second surface of the first portion, the fiber preform further includes a third unidirectional fabric portion and a fourth unidirectional fabric portion, respectively located near the first transverse end and the second transverse end of the first portion.

[0016] The first to fourth unidirectional fabric portions include warp yarns that are not woven with the weft yarns, and each passes through the second and third portions of the fabric.

[0017] - A fiber preform for forming a blade to be manufactured from the fiber preform, the fiber preform comprising: at least one blade airfoil preform portion formed from the first portion of the preform; at least one blade lower platform preform portion formed from the second portion of the preform; at least one blade upper platform preform portion formed from the third portion of the preform; and a wall preform portion formed from the first to fourth unidirectional fabric portions.

[0018] The production of walls via unidirectional yarn layers held by two textile components on either side to form the lower and outer platforms greatly facilitates the shaping of platforms and walls. Therefore, platforms, spoilers, and walls of diverse and complex shapes can be created from a single woven fiber preform. The presence of the unidirectional fabric portion provides relaxation, thus significantly reducing the stress and tension induced in the preform.

[0019] Furthermore, the method of the present invention can eliminate the need for manual cutting during the fiber preform forming process.

[0020] According to a feature of the method of the present invention, the first portion of the blank is passed through the yarn of the second portion of the blank and the yarn of the third portion of the blank.

[0021] According to another feature of the method of the present invention, the fiber preform of the blade further includes a first upstream spoiler preform portion, which is formed by excess length of the second portion of the blank and the first and third unidirectional fabric portions.

[0022] According to another feature of the method of the present invention, the fiber preform further includes: a second upstream spoiler preform portion formed by excess length of the third portion of the blank and the first and third unidirectional fabric portions; and a downstream spoiler preform portion formed by excess length of the third portion of the blank and the second and fourth unidirectional fabric portions.

[0023] According to another feature of the method of the present invention, the first set of warp and weft layers that are bonded together in the first part of the blank also correspond to the root preform portion and the stem preform portion, and the fiber preform that forms the blade to be manufactured includes: the root preform portion and the stem preform portion of the blade formed from the first part (102) of the blank.

[0024] The present invention also relates to a method for manufacturing turbine blades made of composite materials, the method comprising:

[0025] - Turbine blade preforms are manufactured according to the methods used for manufacturing blade fiber preforms;

[0026] - Densification of the preform through a matrix to obtain a blade made of composite material, the blade having at least one blade, at least one lower platform, at least one upper platform and a wall.

[0027] The present invention also relates to a method for manufacturing turbine blades made of composite materials, the method comprising:

[0028] - Turbine blade preforms are manufactured according to the methods used for manufacturing blade fiber preforms;

[0029] - Densification of the preform through a matrix to obtain a blade made of composite material, the blade having a root, a shank, at least one blade, at least one lower platform, at least one upper platform and a wall.

[0030] The present invention also relates to a blade fiber preform for a turbine, the preform having three-dimensional weave or multi-layer weave, integrally comprising at least one airfoil preform portion, at least one lower platform preform portion and at least one upper platform preform portion, the preform further comprising: an upstream wall preform portion and a downstream wall preform portion formed by first to fourth unidirectional fabric portions.

[0031] The present invention also relates to a blade fiber preform for a turbine, the preform having a three-dimensional or multi-layer weave, integrally comprising at least one root preform portion, a shank preform portion and an airfoil preform portion, at least one lower platform preform portion and at least one upper platform preform portion, the preform further comprising: an upstream wall preform portion and a downstream wall preform portion formed by first to fourth unidirectional fabric portions.

[0032] According to a feature of the preform of the present invention, the preform further includes: a first upstream spoiler preform portion, which includes excess length of the first unidirectional fabric portion and the third unidirectional fabric portion.

[0033] According to another feature of the preform of the present invention, the preform further includes: a second upstream spoiler preform portion, which includes excess length of the first unidirectional fabric portion and the third unidirectional fabric portion; and a downstream spoiler preform portion, which includes excess length of the second unidirectional fabric portion and the fourth unidirectional fabric portion.

[0034] According to another feature of the preform of the present invention, the preform further includes a root preform portion and a shank preform portion.

[0035] The present invention also relates to a turbine blade made of composite material, comprising a fiber reinforcement densified by a matrix, the blade comprising at least one airfoil, at least one lower platform, at least one upper platform, and an upstream wall and a downstream wall, the fiber reinforcement comprising a blade fiber preform according to the present invention.

[0036] The present invention also relates to a turbine blade made of composite material, comprising a fiber reinforcement densified by a matrix, the blade including a root, a shank, a blade, at least one lower platform, at least one upper platform, and an upstream wall and a downstream wall, the fiber reinforcement comprising a blade fiber preform according to the present invention.

[0037] The present invention also relates to an aircraft engine comprising a plurality of blades according to the present invention.

[0038] The present invention also relates to an aircraft comprising: an engine according to the present invention. Attached Figure Description

[0039] Figure 1A and Figure 1B This is a schematic perspective view of a blade made of composite material according to an embodiment of the present invention.

[0040] Figure 2A and Figure 2B The diagram illustrates, in a very schematic way, the materials used for production. Figure 1A and Figure 1B The illustration shows an example of the arrangement of three sets of yarn layers and unidirectional fabric portions in a three-dimensional braided fiber preform of a blade fiber preform.

[0041] Figure 3A , Figure 3B , Figure 4A , Figure 4B , Figure 5A and Figure 5B It shows the manufacturing process as follows Figure 1A and Figure 1B The continuous steps of the fiber preform of the blade shown. Detailed Implementation

[0042] This invention is applicable to various types of turbine blades with integrated platforms. It is particularly suitable for fixed compressor blades, i.e., blades without a root and shank. This invention is also applicable to compressor and turbine blades of different gas turbine bodies, such as… Figure 1A and Figure 1B The low-pressure (LP) turbine rotor blade shown.

[0043] Figure 1A and Figure 1BThe blade 10 includes, in a manner known per se,: a blade 20; a root 30 formed of a thicker portion having, for example, a bulbous cross-section, the root extending from a shank 32; a lower platform 40 located near the root 30 and provided with a first upstream overlapping spoiler 41; an upper platform 50 located between the lower platform 40 and the blade 20 and provided with a second upstream overlapping spoiler 51 and a downstream overlapping spoiler 52; and an upstream wall 60 and a downstream wall 70 located between the lower platform 40 and the upper platform 50.

[0044] The vane 20 extends longitudinally between the upper platform 50 and the longitudinal end 21, and the vane 20 has a curved profile with variable thickness between its leading edge 20a and trailing edge 20b in cross-section. In some cases, the longitudinal end 21 may be provided with a cover, spoiler, or blade seal, which are already known in nature. Figure 1A and Figure 1B (Not shown in the image).

[0045] The blade 10 is mounted on the turbine rotor (not shown) by engaging the root 30 into a correspondingly shaped housing arranged around the rotor. The root 30 extends from the shank 32 to connect to the inner (or lower) surface 52 of the upper platform 50.

[0046] At the inner diameter end of the blade 20, the blade 20 is connected to the upper platform 50 on the outer (or upper) surface 53, which defines the flow path of the gas flow in the turbine on the inner side. At the upstream and downstream ends of the lower platform 40 (in the flow direction F of the gas flow), the lower platform 40 is preceded by an upstream overlapping spoiler 41, and the upper platform 50 terminates at the upstream overlapping spoiler 51. In the example shown, the upper platform 50 is inclined, forming a total angle that is non-zero relative to the normal of the longitudinal direction of the blade. Depending on the desired profile of the inner surface of the gas flow, this angle can be zero, or the upper platform can have a generally non-linear (e.g., curved) profile.

[0047] Figure 2A and Figure 2B The fiber preform 100 is shown schematically, from which the blade fiber preform is formed to obtain a composite blade with an integrated platform and cover, such as, after matrix densification and optional machining. Figure 1A and Figure 1B As shown.

[0048] The blank 100 comprises three parts 102, 104, and 106 obtained through three-dimensional weaving or multi-layer weaving, in Figure 2A and Figure 2BOnly the envelopes of these three parts are shown. Part 102 is the part used after forming to form the fiber preform of the blade corresponding to the blade airfoil, stem, and root preforms. Part 104 is the part used after forming to form the fiber preform of the blade corresponding to the lower platform and upstream spoiler preforms of the blade. Part 106 is the part used after forming to form the fiber preform of the blade corresponding to the upper platform and upstream and downstream spoiler preforms of the blade.

[0049] The three parts 102, 104, and 106 are generally arranged in the longitudinal direction D, which corresponds to the longitudinal direction of the blade to be produced. L Extended fiber strip form. Part 102 has a variable thickness in its portion for forming the blade preform, determined according to the profile thickness of the blade to be produced. Part 102 has an excess thickness 103 in its portion for forming the root preform, determined according to the thickness of the root of the blade to be produced. Part 102 along the longitudinal direction D L Extending between the first longitudinal end 102c and the second longitudinal end 102d, along the transverse direction D corresponding to the transverse direction of the blade. T Extending between the first lateral end 102e and the second lateral end 102f, which are respectively used to form the leading and trailing edges of the blade, and along the thickness direction D of the blank. E It extends between the first surface 102a and the second surface 102b, which are used to form the pressure surface and suction surface of the blade, respectively.

[0050] The width of the blank portion 102 is selected based on the length of the root of the blade to be produced and the unfolded profile (plane) of the airfoil, while the blank portions 104 and 106 each have a width greater than I, which is selected based on the unfolded length of the lower platform and upper platform of the blade to be produced.

[0051] The blank portions 104 and 106 have substantially the same width and each has a substantially constant thickness determined according to the thickness of the platform of the blade to be produced. Each of portions 104 and 106 includes: a first portion 104a, 106a extending along and in the vicinity of a first surface 102a of portion 102, and a second portion 104b, 106b extending along and in the vicinity of a second surface 102b of portion 102.

[0052] Parts 104a and 104b of the blank portion 104 are connected by a connecting portion 140c, which extends laterally relative to the blank portion 102 at a position corresponding to the lower platform of the blade to be produced. The connecting portion 140c passes through portion 102 in a direction substantially parallel to the normal to the longitudinal direction of the fiber blank. Parts 106a and 106b of the blank portion 106 are connected by a connecting portion 160c, which extends laterally relative to the blank portion 102 at a position corresponding to the upper platform of the blade to be produced. The connecting portion 160c extends in a direction relative to the longitudinal direction D of the fiber blank. L The normal line passes through the strip in a manner that forms an angle α.

[0053] As described in more detail below, the blank portions 102, 104, and 106 are simultaneously woven in the following manner: on the one hand, a three-dimensional weaving without connection between portions 104a and 104b of blank portion 102 and blank portion 104, and on the other hand, a weaving without connection between portions 106a and 106b of blank portion 102 and blank portion 106, and in the longitudinal direction D. L Multiple continuous blanks 100 are continuously woven on top. There is no connection between sections 104 and 106.

[0054] According to the present invention, the fiber preform 100 further includes, on one side of the first surface 102a of the portion 102 (of the first group of yarn layers): a first unidirectional fabric portion 107 and a second unidirectional fabric portion 108, which are respectively located near the first transverse end 102e and the second transverse end 102f of the portion 102 (of the first group). Figure 2A Furthermore, the fiber preform 100 also includes, on the second surface 102b side of the portion 102 (of the first group), a third unidirectional fabric portion 109 and a fourth unidirectional fabric portion 110, which are located near the first transverse end 102e and the second transverse end 102f of the portion 102 (of the first group), respectively. Figure 2B ).

[0055] The first to fourth unidirectional fabric portions 107, 108, 109 and 110 each include: warp yarns not woven with weft yarns. Each of the unidirectional fabric portions 107, 108, 109 and 110 passes through portions 104 and 106 at the connecting portions 140c and 160c of portions 104 and 106.

[0056] Figure 3A , Figure 3B , Figure 4A , Figure 4B , Figures 5A to 5BThe diagram illustrates, in a highly schematic manner, how a fiber preform with a shape closely resembling the blade to be manufactured is obtained from a fiber blank 100. A fiber portion or strip 102 is cut at one end and the opposite end of a thickened portion 103 to form a strip 120 with a length corresponding to the longitudinal dimension of the blade to be manufactured. This strip has a protrusion 130 formed from a portion of the thickened portion 103 and located at a position corresponding to the root position of the blade to be manufactured.

[0057] Furthermore, cutting is performed in the first portion 104a and the second portion 104b of the blank portion 104 to leave segments 140a and 140b on either side of the connecting portion 140c, such as... Figure 3A and Figure 3B As shown. Similarly, cutting is performed in the first portion 106a and the second portion 106b of the blank portion 106 to leave segments 160a and 160b on either side of the connecting portion 160c, as shown. Figure 3A and Figure 3B As shown. The lengths of sections 140a, 140b and 160a, 160b are determined based on the lengths of the platform and cover in the blade to be manufactured.

[0058] Cutting is also performed in the first to fourth unidirectional fabric portions 107, 108, 109, and 110. More precisely, in the unidirectional fabric portions 107, 108, 109, and 110, a first cut is made at a defined distance below the connecting portion 140c to leave remaining first excess lengths 107a, 108a, 109a, and 110a. In the unidirectional fabric portions 107, 108, 109, and 110, a second cut is made at a defined distance above the connecting portion 160c to leave second excess lengths 107c, 108c, 109c, and 110c. The portions 107b, 108b, 109b and 110b of the unidirectional fabric portions 107, 108, 109b and 110b located between sections 140a and 140b (on the one hand) and between sections 160a and 160b (on the other hand) are used to form the wall preform, as described below.

[0059] Because of the passage between portions 104a and 104b of portion 102 and portion 104 on one hand, and between portions 106a and 106b of portion 102 and portion 106 on the other hand, segments 140a, 140b, 160a, and 160b can be folded back perpendicular to strip 102 without cutting the yarn to form plates 140 and 160, as shown. Figure 4A and Figure 4B As shown. The first excess lengths 107a, 108a, 109a and 110a are folded downwards onto the inner surface 141 of plate 140. Figure 4A and Figure 4B(not shown in the image), while the second excess lengths 107c, 108c, 109c and 110c are folded down onto the outside 162 of the plate 160.

[0060] Then, a fiber preform 200 of the blade to be manufactured is obtained by molding the blank portion 102 to reproduce the curved profile of the blade airfoil. The lower plate 140 is also deformed to reproduce a shape similar to the lower platform of a blade with an upstream overlapping spoiler. Similarly, the plate 160 is deformed to reproduce a shape similar to the upper platform of a blade with upstream and downstream overlapping spoilers, such as... Figure 5A and Figure 5B As shown. Parts 107b and 108b of the unidirectional fabric portions 107 and 108 located between the lower plate 140 and the upper plate 160 are deformed to reproduce a shape similar to the upstream wall of the blade. Parts 109b and 110b of the unidirectional fabric portions 109 and 110 located between the lower plate 140 and the upper plate 160 are deformed to reproduce a shape similar to the downstream wall of the blade.

[0061] Thus, a preform 200 is obtained, which has: a wing preform portion 220; a root preform portion 230; a shank preform portion 250; a lower platform preform portion 240 having an upstream first spoiler preform portion 241; an upper platform preform portion 260 having an upstream second spoiler preform portion 261 and a downstream spoiler preform portion 262; an upstream wall preform portion 270; and a downstream wall preform portion 280.

[0062] The fiber preform 200 is then densified. Densification of the fiber preform used to form the fiber reinforcement of the blade includes filling all or part of the pores in the preform with the material constituting the matrix. This densification can be performed in a manner known per se according to a liquid process (CVL) or gas process (CVI), a ceramic filler injection process (slurry casting), or a silicon alloy impregnation process (MI or RMI), or even in a sequence of one or more of these processes.

[0063] The liquid method involves impregnating a preform with a liquid composition containing a precursor of a matrix material. The precursor is typically in polymer form, such as a high-performance epoxy resin, and optionally diluted in a solvent. The preform is placed in a mold, which can be tightly sealed with a housing having a final molded blade shape. The mold is then closed, and the liquid matrix precursor (e.g., resin) is injected into the entire housing to impregnate the entire fibrous portion of the preform.

[0064] The conversion of the precursor to the matrix (i.e., its polymerization) is carried out by heat treatment, which is typically done by heating the mold after removing any solvent and crosslinking the polymer, while the preform remains in the mold with a shape corresponding to the part to be produced.

[0065] In the case of forming a carbon or ceramic matrix, the heat treatment includes pyrolyzing the precursor to transform the matrix into a carbon or ceramic matrix, depending on the precursor used and the pyrolysis conditions. For example, the ceramic liquid precursor (especially SiC or SiCN) can be a resin of the polycarbosilane (PCS), polytitanium carbosilane (PTCS), or polysilazane (PSZ) type, while the carbon liquid precursor can be a resin with a relatively high coke content, such as a phenolic resin. Several consecutive cycles from impregnation to heat treatment can be performed to achieve the desired degree of densification.

[0066] Especially in the case of forming an organic matrix, the densification of fiber preforms can be achieved using the well-known resin transfer molding (RTM) method. According to the RTM method, the fiber preform is placed in a mold having the shape of the shell to be produced. A thermosetting resin is injected into the interior space of the mold, which contains the fiber preform. Typically, a pressure gradient is established within this interior space between the resin injection point and the resin outlet to control and optimize the impregnation of the preform with the resin.

[0067] Densification of preforms can also be achieved by polymer impregnation and pyrolysis (PIP) or by slurry casting impregnation (e.g., containing SiC and organic binders) followed by liquid silicon infiltration (melt infiltration).

[0068] Fiber preforms can also be densified via chemical vapor infiltration (CVI) of the matrix through a known gaseous pathway. A fiber preform corresponding to the fiber reinforcement of the blade to be produced is placed in a furnace, and a reactive gas phase is introduced into the furnace. The pressure and temperature in the furnace, as well as the composition of the gas phase, are selected to allow the gas phase to diffuse within the pores of the preform, thereby forming a matrix therein by depositing a solid material at the material core in contact with the fibers, resulting from the decomposition of the gas phase components or from the reaction between several components. This contrasts with the inherent pressure and temperature conditions of chemical vapor deposition (CVD), which only results in deposition on the material surface.

[0069] The SiC matrix can be obtained by decomposing methyltrichlorosilane (MTS) to obtain SiC, while the carbon matrix can be obtained by cracking hydrocarbon gases (such as methane and / or propane) to obtain carbon.

[0070] Densification combining liquid and gaseous approaches can also be used to facilitate implementation, limit manufacturing costs and cycles, while achieving satisfactory properties for the intended use.

[0071] The densification process described above can be used to produce components made of composite materials having an organic matrix (OMC), a carbon matrix (C / C), and a ceramic matrix (CMC) from the fiber structure of the present invention.

[0072] In the production of parts made of oxide / oxide composite materials, the fiber structure is impregnated with a slurry filled with refractory oxide particles. After removing the liquid phase from the slurry, the resulting preform is heat-treated to sinter the particles and obtain a refractory oxide matrix. This structure can be impregnated using methods employing pressure gradients, such as injection molding processes known as "RTM" or submicron powder coating known as "APS".

[0073] After densification, the following is obtained: Figure 1A and Figure 1B The composite blade 10 shown includes, at its lower portion, a root 30 formed by a root preform portion 230 of a fiber preform 200, the root extending from a shank 32 formed by a shank preform portion 250 of the preform 200, and the blade 10 includes an aerodynamic winglet or profile 20 formed by a winglet preform portion 220 of the preform 200. The winglet 20 has a leading edge 20a and a trailing edge 20b, corresponding to a first lateral end and a second lateral end of the fiber preform 200, respectively. The blade 10 further includes: a lower platform 40 corresponding to the lower platform preform portion 240 of the preform 200; an upper platform 50 corresponding to the upper preform portion 260 of the preform 200; an upstream wall 60 corresponding to the upstream wall preform portion 270 of the preform 200; a first upstream overlapping spoiler 41 corresponding to the preform portion 241 of the first upstream spoiler 200; a downstream wall 70 corresponding to the downstream wall preform portion 280 of the preform 200; a second upstream overlapping spoiler 51 corresponding to the second upstream spoiler preform portion 261 of the preform 200; and a downstream overlapping spoiler 52 corresponding to the downstream spoiler preform portion 262 of the preform 200.

Claims

1. A method for manufacturing a fiber preform of a turbine blade made of composite material, the method comprising: A fiber preform (100) is formed by three-dimensional or multi-layer weaving between multiple warp and weft yarns, wherein the multiple warp yarns are along a longitudinal direction (D) corresponding to the longitudinal direction of the blade to be produced. L The multi-layered weft yarn extends along a transverse direction (D) corresponding to the transverse direction of the blade to be produced. T )extend, The fiber preform includes: The first group of warp and weft layers are combined together, and the first group is along the longitudinal direction (D). L ) extends between the first longitudinal end and the second longitudinal end, along the said transverse direction (D) T ) extends between the first transverse end (102e) and the second transverse end (102f) respectively used to form the leading and trailing edges of the blade, and along the thickness direction (D) of the fiber preform. E The first set extends between a first surface (102a) and a second surface (102b) respectively used to form the pressure surface and suction surface of the blade, the first set forming a first portion (102) of the fiber preform (100), the first portion (102) corresponding to at least a portion of the blade airfoil; The second set of warp and weft layers, which are at least partially bonded together, form a second portion (104) of the fiber preform, the second portion (104) corresponding to at least a portion of the under-blade platform preform; A third set of warp and weft layers, at least partially bonded together, forms a third portion (106) of the fiber preform, the third portion (106) corresponding to at least a portion of the platform preform on the blade. The yarn of the first portion (102) is not combined with the yarn of the second portion (104) and the third portion (106). The fiber preform (100) further includes, on the first surface (102a) of the first portion (102), a first unidirectional fabric portion (107) and a second unidirectional fabric portion (108), located near the first transverse end (102e) and the second transverse end (102f) of the first portion, respectively; and on the second surface (102b) of the first portion, the fiber preform (100) further includes, a third unidirectional fabric portion (109) and a fourth unidirectional fabric portion (110), located near the first transverse end and the second transverse end of the first portion, respectively. The first to fourth unidirectional fabric portions include warp yarns that are not woven with weft yarns and each passes through the second and third portions of the fiber preform; A fiber preform (200) for manufacturing the blade is formed from the fiber preform, the fiber preform (200) comprising: at least one blade preform portion (220) formed from the first portion (102) of the fiber preform (100); at least one lower platform preform portion (240) formed from the second portion (104) of the fiber preform; at least one upper platform preform portion (260) formed from the third portion (106) of the fiber preform; and an upstream wall preform portion (270) and a downstream wall preform portion (280) formed from a first unidirectional fabric portion to a fourth unidirectional fabric portion.

2. The method according to claim 1, wherein, The first portion (102) of the fiber preform (100) is pierced by the yarn of the second portion (104) of the fiber preform and the yarn of the third portion (106) of the fiber preform.

3. The method according to claim 1, wherein, The lower platform preform part includes an upstream first spoiler preform part (241), which is formed by the second part (104) of the fiber preform (100) and the excess length (107a) of the first unidirectional fabric part (107) and the excess length (108a) of the third unidirectional fabric part (108).

4. The method according to claim 1, wherein, The upper platform preform portion includes: an upstream second spoiler preform portion (261), which is formed by the third portion (106) of the fiber preform (100) and the excess length (107c) of the first unidirectional fabric portion (107) and the excess length (108c) of the third unidirectional fabric portion (108); and a downstream spoiler preform portion (262), which is formed by the third portion (106) of the fiber preform (100) and the excess length (109c) of the second unidirectional fabric portion (109) and the excess length (110c) of the fourth unidirectional fabric portion (110).

5. The method according to any one of claims 1 to 4, wherein, The first set of warp and weft layers that are bonded together in the first portion (102) of the fiber preform (100) also correspond to the root preform portion and the stem preform portion. The fiber preform (200) forming the blade to be manufactured includes: the root preform portion (230) and the stem preform portion (250) formed from the first portion (102) of the fiber preform (100).

6. A method for manufacturing turbine blades (10) made of composite materials, the method comprising: The method according to any one of claims 1 to 4 is used to manufacture turbine blade preforms; The preform is densified by means of a matrix to obtain a blade (10) made of composite material, the blade (10) having at least one blade (20), at least one lower platform (40), at least one upper platform (50) and walls (60, 70).

7. A method for manufacturing turbine blades (10) made of composite materials, the method comprising: The method described in claim 5 is used to manufacture turbine blade preforms; The preform is densified by means of a matrix to obtain a blade (10) made of composite material, the blade (10) having a root (30), a shank (32), at least one blade (20), at least one lower platform (40), at least one upper platform (50) and walls (60, 70).

8. A fiber preform (200) for turbine blades, the fiber preform having a three-dimensional or multi-layered weave, integrally comprising at least one airfoil preform portion (220), at least one lower platform preform portion (240), and at least one upper platform preform portion (260), the fiber preform further comprising: The upstream wall preform portion (270) and the downstream wall preform portion (280) are formed by the first unidirectional fabric portion to the fourth unidirectional fabric portion.

9. The fiber preform according to claim 8 further includes an upstream first spoiler preform portion (241), the upstream first spoiler preform portion (241) including excess length (107a) of the first unidirectional fabric portion (107) and excess length (108a) of the third unidirectional fabric portion (108).

10. The fiber preform according to claim 8, further comprising an upstream second spoiler preform portion (261), the upstream second spoiler preform portion (261) including excess lengths of the first unidirectional fabric portion (107) and the third unidirectional fabric portion (108); and a downstream spoiler preform portion (262), the downstream spoiler preform portion (262) including excess lengths (109c) of the second unidirectional fabric portion (109) and excess lengths (110c) of the fourth unidirectional fabric portion (110).

11. The fiber preform according to any one of claims 8 to 10, further comprising a root preform portion (230) and a shank preform portion (250).

12. A turbine blade (10) made of composite material, comprising a fiber reinforcement densified by a matrix, the blade comprising at least one blade (20), at least one lower platform (40), at least one upper platform (50), and an upstream wall and a downstream wall, the fiber reinforcement comprising a fiber preform according to any one of claims 8 to 10.

13. A turbine blade (10) made of composite material, comprising a fiber reinforcement densified by a matrix, the blade comprising a root (30), a shank (32), a blade (20), at least one lower platform (40), at least one upper platform (50), and an upstream wall and a downstream wall, the fiber reinforcement comprising a fiber preform according to claim 11.

14. An aircraft engine comprising: Multiple blades according to claim 12 or multiple blades according to claim 13.

15. An aircraft comprising: At least one engine according to claim 14.

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