Tool and method for manufacturing a composite blade for aircraft engine

Abstract

Tool (40) for manufacturing a bucket (10) made of composite material for a turbomachine, in particular a turbomachine of an aircraft, comprising:-a mould (30) and a counter-mould (34) defining between them a cavity (32) configured to receive a woven preform, the cavity (32) having a first portion (Z1) and a second portion (Z2), the first portion is configured to receive the shield (22) and at least one edge of the preform and the second portion is configured to receive at least a portion of the remaining portion of the preform,-an element (42, 44, 46) for managing the temperature of the cavity (32), these elements are configured to heat the first and second portions (Z1, Z2) of the cavity (32) at different temperatures during at least one step of the method for manufacturing the vane (10).

Description

Technical Field

[0001] The present invention relates to a tool and a method for manufacturing a composite blade for an aircraft turbine. Background Art

[0002] The prior art includes in particular documents FR-A1-2 956 057, FR-A1-3 029 134, FR-A1-3 051 386 and EP-A2-2 353 830.

[0003] The use of composite materials is advantageous in the aerospace industry, particularly since these materials offer excellent mechanical properties at relatively low weight.

[0004] One method for manufacturing composite parts for the aerospace industry that is well known to those skilled in the art is the Resin Transfer Molding (RTM) method.

[0005] This is a method for manufacturing composite parts based on resin-impregnated fibers. This method is used, for example, in the manufacture of fan blades and comprises several successive steps.

[0006] First, the fibers are woven together to produce a three-dimensional preform blank, which is then cut to produce a preform roughly in the shape of the blade to be manufactured. The preform is then arranged in a tool comprising a mold and a counter-mold. The tool is closed and liquid resin is injected, maintaining pressure on the injected resin while polymerizing the part by heating the tool.

[0007] The resin used is a very flowable resin which is able to penetrate the preform fibers well even when injected under reduced pressure. During polymerization, under the action of heat, the injected resin successively changes from a liquid state to a gel state and finally to a solid state.

[0008] To manufacture a blade, such as a blade for a turbine fan, a preform is three-dimensionally woven and then impregnated with resin to form a blade that includes a pressure side and a suction side extending from the leading edge to the trailing edge of the blade.

[0009] The composite material of the blade is relatively fragile and particularly sensitive to impacts and it is known to protect the blade by means of a metal shroud which is attached and fixed to the leading edge of the blade.

[0010] The shroud can be attached to the blade in a number of ways. The first way is to bond the shroud to the blade after the resin has polymerised. The adhesive is therefore in the form of a paste or film.

[0011] In current technology, mating the shroud to the edge of the bucket is a critical and demanding step in the manufacturing method. In fact, the shroud is a highly complex component and each shroud may vary according to the manufacturer and manufacturing tolerances and may therefore have different geometrical characteristics.

[0012] Therefore, before matching and bonding the shroud to the edge of the blade, it is necessary to ensure that the size and shape of the shroud matches the size and shape of the blade to optimize the bonding surface and therefore the material health of the bonded parts (adhesive thickness, porosity, etc.).

[0013] By eliminating the bonding step and integrating it directly in the injection step, the geometry of the bonding interface directly matches the geometry of the blade edge at each point, eliminating the steps involved in finding the best shroud / pairing blade edge. This also eliminates the need to prepare the surface of the blade before bonding. Last but not least, this means that additional passages in the heat treatment equipment (oven, autoclave, etc.) are no longer necessary.

[0014] Another way of attaching the shroud to the blade consists in attaching the shroud by co-molding with an already manufactured fiber preform. An adhesive is placed between the shroud and the preform, and the assembly is placed in a tool. The injected resin impregnates the preform, and the curing and pressurization steps ensure that the adhesive and resin polymerize and harden.

[0015] The curing cycle must be adapted to take into account the physical properties of both the binder and the resin and the processing conditions. This limitation requires the development of a complex process that is difficult to industrialize.

[0016] A thermal compromise has to be found to guarantee the physical and chemical robustness of the process as well as the mechanical properties of the final component.

[0017] When mentioning adhesives, it is important to note that:

[0018] - without deteriorating the rheological properties to ensure wetting of the surfaces to be bonded,

[0019] - Ensure that the viscosity is relatively high before applying pressure in the tool, and

[0020] - Not allowing the adhesive to age prematurely at a temperature that guarantees the final mechanical properties of the adhesive joint.

[0021] The important things to know about resin are:

[0022] - ensuring low viscosity to fill the tool cavity and impregnate the preform, and thus ensuring sufficient temperature of the tool, and

[0023] - Before applying pressure in the tool, ensure that the polymerization rate is as low as possible.

[0024] The present invention provides an improvement over the current technology which provides a solution to at least some of the problems discussed above. Summary of the invention

[0025] The invention proposes a tool for manufacturing a blade made of composite material for a turbomachine, in particular an aircraft turbomachine, the blade comprising a blade comprising a pressure side and a suction side extending from the leading edge to the trailing edge of the blade, the blade also comprising a root and an upper edge opposite the root of the blade, the blade also comprising at least one metal shroud extending along at least one of said edges of the blade, the tool comprising:

[0026] a mold and a countermold defining between them a cavity configured to receive a braided preform of a blade, the cavity comprising a first portion configured to receive the shroud and one or more edges of the preform intended to receive the shroud, and a second portion configured to receive at least a portion of the remainder of the preform,

[0027] - at least one opening for injecting resin into the cavity in order to impregnate the preform, and

[0028] - elements for managing the temperature of the chamber,

[0029] It is characterized in that the temperature management element includes a first element for managing the temperature of a first part of the cavity and a second element for managing the temperature of a second part of the cavity, and the second element is independent of the first temperature management element, so that the first management element and the second management element can heat the first part and the second part of the cavity to different temperatures during at least one step of the method for manufacturing the blade.

[0030] Therefore, the tool according to the invention comprises independent temperature management elements, which are configured to bring the first part and the second part of the cavity to a certain temperature respectively. It will be understood that the temperature of the part of the cavity containing the one or more edges and the adhesive can be adapted to facilitate the diffusion of the resin into the preform while avoiding accelerated aging of the adhesive, and the temperature of the other parts of the cavity can be adapted to facilitate the diffusion of the resin while optimizing the polymerization conditions of the resin.

[0031] In the present application, temperature "management" means heating and / or cooling. Thus, the component is capable of heating the tool and the cavity and / or cooling the tool and the cavity. As an example, the first management component is a heating and / or cooling component and the second management component is a heating component.

[0032] The tool according to the invention may include one or more of the following features, taken independently of one another or in combination with one another:

[0033] - the second temperature management element is a heating element configured to heat the tool to a predetermined temperature T1;

[0034] the first temperature management element is a heating element configured to heat the tool to a predetermined temperature, referenced as T1, during one step of the manufacturing method and to heat the tool to another predetermined temperature, referenced as T2 and lower than T1, during another step of the manufacturing method;

[0035] the first temperature management element is a cooling and heating element configured to heat the tool to a predetermined temperature, referenced as T1, during one step of the manufacturing method and to cool the tool to a predetermined temperature, referenced as T2 and lower than T1, during another step of the manufacturing method;

[0036] - the cavity comprises an intermediate portion between the first portion and the second portion, the temperature management element being configured to create a region of gradual temperature transition at the intermediate portion;

[0037] - The temperature management element is a resistance heating type, an induction type or a heat transfer fluid circulation type temperature management element;

[0038] - Temperature management elements distributed throughout the mould and counter-mould; and

[0039] - Temperature management elements are integrated in the mould and the counter-mould; a first temperature management element may be arranged at a first part of the cavity and a second temperature management element may be arranged at a second part of the cavity.

[0040] The invention also proposes a method for manufacturing a composite blade for a turbomachine, in particular a turbomachine for an aircraft, the blade comprising a blade comprising a pressure side and a suction side extending from the leading edge to the trailing edge of the blade, the blade also comprising a root and an upper edge opposite the root of the blade, the blade also comprising at least one metal shroud extending along at least one of said edges of the blade, the method using a tool as described above, and the method comprising the following steps:

[0041] a) arranging a shield and a preform made by weaving fibers in a cavity of a tool, inserting a polymerizable adhesive between the shield and one or more edges of the preform intended to receive the shield, positioning the shield and one or more edges of the preform in a first portion of the cavity and positioning the remainder of the preform in a second portion of the cavity,

[0042] b) close the tool, and

[0043] c) managing the temperature of the tool and injecting a polymerizable resin into the cavity of the tool so that the polymerizable resin impregnates the preform to form the blade after curing,

[0044] Characterized in that step c) comprises:

[0045] c1) a first resin injection sub-step, during which the second portion of the cavity is heated to a predetermined temperature referenced T1 and the first portion of the cavity is managed not to exceed a predetermined temperature referenced T2 and lower than T1, and

[0046] c2) A second curing sub-step, during which the first part and the second part are heated to a temperature T1 .

[0047] The method according to the invention may comprise one or more of the following steps or features, which may be taken independently of each other or in combination with each other:

[0048] - in sub-step c1), the first portion of the cavity is heated to a predetermined temperature T2; it is therefore understood that this first portion is transferred from a temperature below T2 to the temperature T2 by heating;

[0049] - in sub-step c1), the first portion of the cavity is cooled so as not to exceed a predetermined temperature T2; it will therefore be understood that this first portion tends to heat up to above T2 and to be cooled so as not to exceed this temperature;

[0050] - temperature T1 is greater than or equal to 160°C, preferably greater than or equal to 180°C, and temperature T2 is between 80°C and 140°C, preferably between 100°C and 130°C;

[0051] - The weaving of the preform is performed in two or three dimensions. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Further features and advantages of the present invention will become apparent from the following detailed description and for understanding of the detailed description refer to the accompanying drawings, in which:

[0053] [ Figure 1 ] Figure 1 is a schematic perspective view of a composite aircraft turbine blade,

[0054] [ Figure 2 ] Figure 2 The method for manufacturing a blade (e.g. Figure 1 A block diagram of the steps of the method of the blade shown in FIG.

[0055] [ Figure 3 ] Figure 3is a schematic perspective view of the mold in which the preform and the shield will be arranged and into which the resin will be injected.

[0056] [ Figure 4 ] Figure 4 is shown for manufacturing according to Figure 1 A graph of the tool temperature evolution of the impeller over time and showing two heating cycles,

[0057] [ Figure 5 ] Figure 5 is a schematic cross-sectional view of a tool according to one embodiment of the present invention;

[0058] [ Figure 6 ] Figure 6 is a schematic cross-sectional view of a tool according to an alternative embodiment of the present invention;

[0059] [ Figure 7 ] Figure 7 is shown for making Figure 1 A graph showing the temperature of a tool for a bucket as a function of time is shown and illustrates the manufacturing method according to the invention. DETAILED DESCRIPTION

[0060] Reference Figure 1 , Figure 1 A composite blade 10 for a turbomachine is shown, such as a fan blade or, in the case of a turbofan engine, a secondary flow straightener blade.

[0061] The bucket 10 comprises a blade 12 connected by a post 14 to a root 16 , for example dovetail-shaped and shaped to engage in a recess of complementary shape in a rotor disk to retain the bucket on the disk.

[0062] The blade 12 comprises a leading edge 12a and a trailing edge 12b for gases flowing in the turbine. The blade 12 comprises a curved or twisted aerodynamic profile and comprises a pressure side 18 and a suction side 20 extending between the leading edge 12a and the trailing edge 12b. The blade 12 also comprises an upper edge 12c opposite the root 16.

[0063] The blade 12 is made of a fiber preform obtained by weaving fibers (eg carbon). The weaving may be a two-dimensional weaving, preferably a three-dimensional weaving.

[0064] The leading edge 12a of the blade is reinforced and protected by a metal shroud 22 fixed to the leading edge 12a. The shroud 22 is made of, for example, a nickel and cobalt-based alloy, titanium, stainless steel or the like.

[0065] The following description relates to attaching the shroud 22 to the leading edge 12a. By analogy, it is understood that the shroud 22 or another shroud can be attached to the trailing edge 12b. It is also understood that the shroud 22 or another shroud can be attached to the top edge 12c. In addition, for example, the shroud provided on the trailing edge 12b can extend up to, for example, the upper edge 12c, or the shroud of the trailing edge 12b and the upper edge 12c can be formed as a single piece. Therefore, even if the following description is made with respect to the shroud located on the leading edge 12a of the blade 12, several variations can be envisaged within the meaning of the invention with respect to the number and position of the shrouds.

[0066] In the present invention, the shield 22 is fixed first by co-molding the preform with the shield 22 and second by bonding the shield 22 using the adhesive 26 .

[0067] Figure 2 is a diagram showing a method for manufacturing a composite blade 10 (eg Figure 1 Flowchart of the steps in a method of composite blades shown.

[0068] The method comprises step a), step b) and step c).

[0069] The first step a) of the method comprises manufacturing a fiber preform by weaving the fibers, preferably in three dimensions, using, for example, a Jacquard-type loom. The output preform obtained is a raw untreated preform and may, for example, undergo operations such as cutting, shaping or compression.

[0070] The first step a) also comprises depositing an adhesive 26 between the shroud 22 and the edge 12a of the preform 24, and then placing the assembly thus obtained in a mold 30 for manufacturing a blade (e.g. Figure 3 26 can be applied, for example, by a brush or sprayer. Alternatively, the adhesive can be in the form of a paste. Preferably, the adhesive is in the form of an adhesive film (e.g., a pre-impregnated fabric) that is cut into the desired shape and then applied to the leading edge by an operator before mating the shield to the leading edge.

[0071] Preferably, the adhesive 26 comprises a thermosetting resin impregnated with an epoxy resin (e.g. or Adhesive film for a woven carrier portion of a product sold by

[0072] The shield 22 is generally dihedral in shape and defines a V-shaped groove into which the edge of the preform 24 is inserted. Adhesive 26 may be deposited in the groove of the shield 22 and / or on the edge of the preform 24.

[0073] Then, the preform 24 equipped with the adhesive 26 and the shield 22 is arranged in the mold 30 ( Figure 3 ). The mold 30 forms part of a tool that also includes a counter-mold (not shown). The mold 30 and the counter-mold have complementary shapes and define between them a cavity 32 for receiving the preform 24 and the shroud 22. A portion or half of the cavity 32, for example intended to form the pressure side 18 of the blade 12, is formed in the mold 30, and another portion or half of the cavity 32, for example intended to form the suction side 20 of the blade 12, is formed in the counter-mold.

[0074] In step b), the tool is closed by arranging the countermold on the mold 30 and holding the countermold and the mold 30 tightly together, in particular to ensure that the cavity 32 is watertight.

[0075] The method then comprises a step c) of temperature-managing the tool and injecting a polymerizable resin into the cavity of the tool so that the polymerizable resin impregnates the preform 24 to form a blade after curing.

[0076] The management of the tool, in particular the heating thereof, is performed by temperature management elements. These management elements may form part of the oven or the autoclave and / or may be directly integrated in the mould and / or the counter-mould of the tool.

[0077] The resin injected into the tool is intended to impregnate the preform 24 and come into contact with the adhesive 26 of the shroud 22. Once the resin has polymerized and hardened, the shroud 22 is attached to the blade 12 using the adhesive 26 and the resin.

[0078] After polymerization of the resin, the bucket 10 thus obtained is advantageous since its shroud 22 is perfectly positioned and held on the blade 12 .

[0079] The resin is, for example, an epoxy-based thermosetting resin, a polyimide-based resin or a bismaleimide-based resin. These resins are commercially available.

[0080] Therefore, the adhesive 26 and the resin are made of two different materials having different temperature-dependent physicochemical and rheological properties.

[0081] Figure 4is a graph showing two different tool heating cycles. Heating cycle C2 shows an "ideal" cycle for good behavior of adhesive 26 and optimal bonding of shield 22 to leading edge 12a. Heating cycle C1 shows an "ideal" cycle for optimal resin injection and diffusion in cavity 32 of the tool. It can be noted that cycles C1, C2 each include a similar first portion A of temperature rise (cycle C1, left sloping portion of cycle C2), and an equally similar final portion F of temperature drop (cycle C1, right sloping portion of cycle C2). However, cycles C1 and C2 have different holding temperature steps B, C and E. Cycle C1 includes a first step B at 160°C, followed by a second step C at 180°C, while cycle C2 includes a step D at 150°C, which is reached after a preliminary portion D (immediately after first portion A) of temperature rise at a lower heating rate.

[0082] It can therefore be noted that it is preferred to optimize the heating of the tool to take into account the different physicochemical behaviors of the adhesive 26 and the resin. This is exactly what the present invention proposes, which has a tool that enables this to be achieved.

[0083] Figure 5 A first embodiment of a tool 40 according to the invention is shown very schematically. The tool 40 comprises:

[0084] a mold 30 and a countermold 34 defining between them a cavity 32 configured to receive a braided preform of a blade (such as described above), the cavity 32 comprising a first portion Z1 configured to receive the shroud 22 and the leading edge 12a of the preform, and a second portion Z2 configured to receive at least a portion of the remainder of the preform 24,

[0085] at least one opening 36 for injecting resin into the cavity 32 of the tool 40 in order to impregnate the preform 24 , and

[0086] Temperature management elements 42 , 44 , which are preferably integrated in the mold 30 and the counter-mold 34 .

[0087] According to the invention, the temperature management elements 42 , 44 comprise a first management element 42 arranged at the first portion Z1 of the cavity 32 and a second management element 44 arranged at the second portion Z2 of the cavity 32 and independent of the first management element 42 .

[0088] As can be seen in the figures, the management elements 42 , 44 are advantageously distributed in the mold 30 and in the counter-mold 34 .

[0089] In the example shown, the second management element 44 is a heating element configured to heat the tool 40 to a predetermined temperature T1 . T1 is, for example, greater than or equal to 160°C, preferably greater than or equal to 180°C.

[0090] The first management element 42 may be a heating element configured to heat the tool 40 to a temperature T1 during one step of the manufacturing method and to heat the tool 40 to another predetermined temperature T2 below T1 during another step of the manufacturing method. T2 is, for example, between 80°C and 140°C, preferably between 100°C and 130°C.

[0091] Alternatively, these first management elements 44 may be cooling and heating elements configured to heat the tool to a temperature T1 during one step of the manufacturing method and to cool the tool to a temperature T2 during another step of the manufacturing method.

[0092] In yet another variant, only the first element 42 is integrated in the tool and is a cooling element. The tool 40 is intended to be arranged in a hot press, an oven or an autoclave for heating. When the first element 42 is activated by the circulation of a heat transfer fluid, the zone Z1 is cooled so as not to exceed the temperature T2, while the zone is heated to the temperature T1. When the first element 42 is not activated, the zones Z1 and Z2 are heated to the temperature T1.

[0093] These management components can be electrical or fluidic. For example, these management components can be electric heating elements or induction systems (both of which can only heat), or heat transfer fluid pipes (heat transfer fluid pipes can heat or cool).

[0094] exist Figure 6 In the embodiment shown, in addition to the sections Z1 and Z2, the chamber 32 comprises an intermediate section Z3 between the first section Z1 and the second section Z2. The temperature management element is configured to create a zone of gradual temperature transition at the intermediate section Z3. The intermediate section Z3 may be equipped with its own temperature management element 46.

[0095] Reference Figure 2 The present invention also relates to a method for manufacturing a blade, wherein step c) comprises:

[0096] c1) a first resin injection sub-step, during which the second portion Z2 of the cavity 32 is heated to a temperature T1 and the first portion Z1 of the cavity 32 is managed so as not to exceed the temperature T2, and

[0097] c2) A second curing sub-step, during which the first part Z1 and the second part Z2 are heated to a temperature T1 .

[0098] During sub-step c1), the first portion Z1 of the cavity 32 may be heated to a predetermined temperature T2. Alternatively, the first portion Z1 of the cavity 32 is cooled so as not to exceed the predetermined temperature T2.

[0099] Figure 7 is a graph showing two different heating cycles of a tool 40 according to the present invention.

[0100] The heating cycle C3 is a heating cycle performed by the second management member 44 and therefore represents a heating cycle of the portion Z2 of the cavity 32 that does not include the shield 22 and the adhesive 26. Figure 4 By comparing the curve diagram in , it can be noted that this cycle corresponds to the ideal heating cycle C1 for injecting resin.

[0101] The heating cycle C4 is a heating cycle performed by the first management member 42 and therefore represents a heating cycle of the portion Z1 of the cavity 32 comprising the shield 22 and the adhesive 26. These cycles C3, C4 are superimposed, except for the moment or time interval ΔT of resin injection and diffusion.

[0102] During this sub-step c1), the first part Z1 of the cavity is heated and / or cooled to a temperature T2. This temperature may vary and is 100°C in the example shown for the cycle C4 and 130°C (temperature T2') for the variant C4' of this cycle shown in dashed lines.

[0103] The method according to the invention makes it possible to keep the adhesive as cool as possible to prevent it from creeping when the resin is injected, while sufficiently heating the rest of the cavity to ensure that the resin is sufficiently liquefied to optimize the diffusion of the resin. Since these two constraints are opposing, the invention provides a compromise by creating different temperature management zones in the tool, which increases the freedom of definition of the heating cycle and therefore facilitates its development.

Claims

1. A tool (40) for manufacturing a blade (10) made of composite material for a turbomachine, in particular an aircraft turbomachine, the blade (10) comprising a blade (12), the blade comprising a pressure side (14) and a suction side (16) extending from a leading edge (12a) to a trailing edge (12b) of the blade, the blade further comprising a root (16) and an upper edge (12c) opposite the root (16) of the blade, the blade further comprising at least one metal shroud (22) extending along at least one of the edges (12a, 12b, 12c) of the blade (12), the tool (40) comprising: a mold (30) and a countermold (34), said mold and said countermold defining between them a cavity (32) configured to receive a braided preform of said blade (12), said cavity (32) comprising a first portion (Z1) configured to receive said shield (22) and one or more edges (12a, 12b, 12c) of said preform intended to receive said shield (22), and a second portion (Z2) configured to receive at least a portion of the remainder of said preform, - at least one opening (36) for injecting resin into the cavity (32) in order to impregnate the preform, and - elements (42, 44, 46) for managing the temperature of the chamber (32), Characterized in that the temperature management element (42, 44, 46) comprises a first element (42) for managing the temperature of a first portion (Z1) of the cavity (32) and a second element (44) for managing the temperature of a second portion (Z2) of the cavity (32), the second element being independent of the first temperature management element (42), so that the first management element and the second management element (42, 44) are capable of heating the first portion and the second portion (Z1, Z2) of the cavity (32) to different temperatures during at least one step of the method for manufacturing the blade (10).

2. The tool (40) according to claim 1, wherein: The second temperature management element (44) is a heating element configured to heat the tool (40) to a predetermined temperature, designated T1.

3. The tool (40) according to claim 1 or 2, wherein: The first temperature management element (42) is a heating element configured to heat the tool (40) to a predetermined temperature, designated T1, during one step of the manufacturing method, and to heat the tool to another predetermined temperature, designated T2 and lower than T1, during another step of the manufacturing method.

4. The tool (40) according to claim 1 or 2, wherein: The first temperature management element (42) is a cooling and heating element configured to heat the tool (40) to a predetermined temperature, labeled T1, during one step of the manufacturing method, and to cool the tool (40) to a predetermined temperature, labeled T2 and lower than T1, during another step of the manufacturing method.

5. The tool (40) according to any one of the preceding claims, wherein: The cavity (32) includes a middle portion (Z3) between the first and second portions (Z1, Z2), and the temperature management element (42, 44, 46) is configured to create a zone of gradual temperature transition at the middle portion (Z3).

6. The tool (40) according to any one of the preceding claims, wherein: The temperature management element (42, 44, 46) is a resistance heating type, an induction type or a heat transfer fluid circulation type temperature management element.

7. The tool (40) according to any one of the preceding claims, wherein: The temperature management elements (42, 44, 46) are distributed in the mold (30) and the counter mold (34).

8. The tool (40) according to any one of the preceding claims, wherein: The temperature management elements (42, 44, 46) are integrated into the mold (30) and the counter-mold (34).

9. A method for manufacturing a composite blade (10) for a turbomachine, in particular an aircraft turbine, the blade comprising a blade (12), the blade comprising a pressure side (14) and a suction side (16) extending from a leading edge (12a) to a trailing edge (12b) of the blade, the blade further comprising a root (16) and an upper edge (12c) opposite the root (16) of the blade, the blade further comprising at least one metal shroud (22) extending along at least one of the edges (12a, 12b, 12c) of the blade (12), the method using a tool (40) according to any one of the preceding claims, and comprising the following steps: a) arranging a shield (22) and a preform (24) made by weaving fibers in a cavity of the tool (40), inserting a polymerizable adhesive (26) between the shield (22) and one or more edges (12a, 12b, 12c) of the preform intended to receive the shield (22), positioning the shield (22) and one or more edges of the preform in a first portion (Z1) of the cavity (32), and positioning the rest of the preform in a second portion (Z2) of the cavity, b) closing the tool (40), and c) managing the temperature of the tool (40) and injecting a polymerizable resin into the cavity (32) of the tool so that the polymerizable resin impregnates the preform to form the blade (12) after curing, Characterized in that step c) comprises: c1) a first resin injection sub-step, during which the second portion (Z2) of the cavity (32) is heated to a predetermined temperature referenced T1 and the first portion (Z1) of the cavity (32) is managed not to exceed a predetermined temperature referenced T2 and below T1, and c2) A second curing sub-step, during which the first and second parts (Z1, Z2) are heated to a temperature T1.

10. The method according to claim 9, wherein: In sub-step c1), the first portion (Z1) of the cavity (32) is heated to a predetermined temperature T2.

11. The method according to claim 9, wherein: In sub-step c1), the first portion (Z1) of the cavity (32) is cooled so as not to exceed a predetermined temperature T2.

12. The method according to any one of claims 9 to 11, wherein: The temperature T1 is greater than or equal to 160°C, preferably greater than or equal to 180°C, and the temperature T2 is between 80°C and 140°C, preferably between 100°C and 130°C.

13. The method according to any one of claims 9 to 12, wherein: The weaving of the preform is performed in two or three dimensions.

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