Manufacturing process of a composite part

Abstract

A method for manufacturing at least one composite part intended to be mounted in an aircraft structure, the method comprising: a step of forming at least one peripheral cutout in a stack (1) of at least one ply of reinforcing fibers impregnated in a polymer resin so as to define at least one main portion (3) and one auxiliary portion (4) extending externally to the main portion (3) with respect to the peripheral cutout (2); a step of applying at least one insulating member (5) to an inner edge (41) of the auxiliary portion (4) and / or to an outer edge (31) of the main portion (3); and a step of consolidating (E4) by thermocompression of the stack so as to form the composite part directly to finished dimensions from the main portion (3). Abstract figure: Figure 5

Description

Title of the invention: Method for manufacturing a composite part Technical field

[0001] The present invention relates to the field of manufacturing composite parts and more particularly aims at a method of manufacturing a composite part, comprising reinforcing fibers impregnated in a polymer resin, intended to be mounted in an aircraft.

[0002] As is known, to manufacture a part from composite material, a reinforcing fabric (for example a woven carbon fiber reinforcement) is impregnated with thermoplastic or thermosetting polymer resin to form a pre-impregnated fabric, commonly referred to as a "pre-preg". A stack of several pre-impregnated fabrics is then produced during a "draping" operation. Such an EMP stack is shown in [Fig. 1]. The stack is then cut to the desired dimensions and placed in a mold M (shown in [Fig. 2]) to give the part to be manufactured its final shape. In practice, the entire mold and stack are placed under vacuum and pressure at high temperature (for example in an autoclave) to polymerize the polymer resin and harden the composite material in the mold. The formed composite part is then demolded.

[0003] However, as shown in [Fig. 2], representing a side view of the EMP stack, the pressure P applied during polymerization causes the appearance of a deformation Q on the edges of the EMP stack. Such a deformation Q is known to those skilled in the art under the designation "squeezing effect" and can affect the mechanical performance of the manufactured composite part.

[0004] Also, to overcome this drawback, as shown in [Fig.l], it is known in current processes to firstly manufacture a rough part EB, the dimensions DB of which are larger than the dimensions DF of the finished part F. After polymerization, the rough part EB is machined and trimmed, in order to remove the deformed portion Q and form the finished part 1 with the expected dimensions DF and the edges of which are clean. In a known manner, to carry out such machining, the rough part EB is fixed to a tool and placed under vacuum on the tool so as to be clamped to ensure the absence of any risk of untimely movement under the effect of the machining pressure. The clamped rough part EB is then machined so as to eliminate the edges which have undergone the wringing effect.

[0005] However, such a method has many disadvantages. Indeed, the machining process is long and tedious and significantly increases manufacturing times. In addition, machining requires heavy, bulky and complex tooling to hold the rough part stationary. Furthermore, the tooling must be specifically adapted specifically to the part that needs to be cut out, in particular, the circulation channels under the part to create the vacuum. Also, it is necessary to form several tools to adapt to different parts, which is complex and tedious. The machining machine also has the disadvantage of being energy-intensive and requiring various consumables such as lubricant for example, which increases costs. Finally, machining is generally carried out using a numerically controlled machine. It is then necessary to create a machining program for each part, which is once again long and tedious.

[0006] The invention thus aims to eliminate at least some of these drawbacks by proposing a method for manufacturing a composite part for an aircraft that is fast and efficient. The method according to the invention aims in particular to avoid the intermediary of a first rough part and its machining and to directly form the final composite part. PRESENTATION OF THE INVENTION

[0007] The invention relates to a method for manufacturing at least one composite part intended to be mounted in an aircraft structure, the composite part being produced by consolidating a stack of at least one ply of reinforcing fibers impregnated in a polymer resin, the composite part having predetermined finished dimensions to allow its mounting in the aircraft, gross dimensions of the composite part being predetermined to result, after consolidation, in the finished dimensions of the composite part. The method comprises: • a step of forming at least one peripheral cutout in the stack so as to define: • at least one main portion comprising an outer edge, the peripheral cutting being carried out in such a way that the main portion has the gross dimensions, • an auxiliary portion comprising an inner border, the auxiliary portion extending outwardly from the main portion with respect to the peripheral cutout, • a step of applying at least one insulating member to the inner edge of the auxiliary portion and / or to the outer edge of the main portion so that the insulating member separates the inner edge and the outer edge to prevent the mixing of the polymer resins of the main portion and the auxiliary portion, and • a step of consolidation by thermocompression of the stack so as to form the composite part directly to the finished dimensions from the main portion, the consolidated auxiliary portion being capable of being separated from the composite part at the peripheral cut.

[0008] The manufacturing method according to the invention advantageously makes it possible to manufacture the composite part with finished dimensions directly after the consolidation step, simply by separating the consolidated main portion and the consolidated auxiliary portion, without it being necessary to trim the stack in which the resin has polymerized. Indeed, thanks to the auxiliary portion at the periphery of the main portion, the outer edge of the main portion has advantageously not undergone any wringing effect and therefore no deformation.

[0009] The expression "consolidation by thermocompression" means thermocompression in an autoclave or in a heating press.

[0010] The insulating member applied and positioned at the peripheral cutout between the main portion and the auxiliary portion advantageously makes it possible during the consolidation operation to prevent the polymer resins of each portion from mixing and crystallizing together. This makes it possible to polymerize each portion independently and to separate them in turn, simply and quickly, without the need for special tools.

[0011] A peripheral cut before crosslinking the polymer resin is simpler and faster to carry out, since it is not necessary to clamp the stack on a specific tool. The method according to the invention thus allows a significant saving of time. It is also not necessary to manufacture a specific tool for each composite part to be manufactured, which is particularly advantageous and makes it possible to significantly limit production costs.

[0012] In addition, avoiding machining after consolidation makes it possible to avoid forming a rough part with dimensions larger than the finished dimensions of the composite part to allow subsequent trimming to the correct dimensions, which significantly limits the quantities of material required for manufacturing the composite part. Cutting the stack before consolidation also makes it possible to produce a fine cut (unlike a milling cutter used for machining), which makes it possible to limit material losses or the scrapping of portions damaged by machining.

[0013] Preferably, the manufacturing method is free from a step of machining the composite part after the separation of the composite part and the consolidated auxiliary portion, which represents a saving of time and a limitation of costs. Indeed, this makes it possible to avoid the manufacturing, storage and management of different tools for each composite part to be manufactured, while limiting energy consumption (particularly important for a machining machine) and also avoiding the need to create a machining program for each part, which is long and tedious.

[0014] In one embodiment, the insulating member has an adhesive surface intended to be in contact with the main edge or the auxiliary edge and an opposite non-stick surface. The insulating member thus adheres to one of the edges to retain the polymer resin during the consolidation step. The portion of the stack on which the insulating member is applied is also easy to handle. The opposite non-stick surface makes it possible to juxtapose the main portion and the auxiliary portion without difficulty, since the insulating member does not adhere to the portion on which it is not applied.

[0015] Preferably, the insulating member is a polytetrafluoroethylene type adhesive tape. Such an adhesive tape, known by the acronym "PTFE", advantageously makes it possible to effectively insulate the main portion and the auxiliary portion while having mechanical characteristics capable of withstanding the temperatures and pressures experienced during the consolidation step.

[0016] Preferably, the peripheral cutting is carried out by ultrasonic cutting. The ultrasound makes it possible to form a fine cut which makes it possible not to affect the predetermined dimensions of the composite part. Indeed, the stack comprising a raw or “raw” polymer resin, that is to say unpolymerized, the latter is more flexible and simpler to cut. Thus, it is advantageously not necessary to use, for example, a machining machine with a milling cutter to carry out a trimming, as was the case in the prior art. Ultrasonic cutting can easily be carried out manually by an operator.

[0017] In one embodiment, the method being configured to manufacture a plurality of composite parts intended to be mounted in an aircraft structure and each having predetermined finished dimensions to allow its mounting in the aircraft and predetermined gross dimensions to result, after consolidation, in the finished dimensions of the composite part, the forming step is carried out so as to form a plurality of peripheral cutouts in the stack so as to define: • a plurality of main portions each comprising an outer edge, each peripheral cut being made so that each main portion has the gross dimensions, • an auxiliary portion comprising a plurality of interior borders, the auxiliary portion extending externally to each main portion with respect to each peripheral cutout, • the step of applying at least one insulating member being carried out on each inner edge of the auxiliary portion and / or on each outer edge of each main portion so that the insulating member separates the inner edges respectively from the outer edges to prevent the mixing the polymer resins of each main portion and the auxiliary portion, and • the stack consolidation step being carried out so as to form each composite part directly to the finished dimensions from each main portion, the consolidated auxiliary portion being able to be separated from the composite parts at the level of each peripheral cut.

[0018] The method thus makes it possible in the same stack to manufacture several composite parts from several main portions cut from the stack and each separated from the auxiliary portion by an insulating member, which represents a significant time saving. The peripheral cutting being carried out before consolidation and therefore being finer makes it possible to form a greater number of main parts in the same stack, which makes it possible to limit both production times and costs.

[0019] In one embodiment, the method being configured to manufacture a plurality of composite parts intended to be mounted in an aircraft structure and each having predetermined finished dimensions to allow its mounting in the aircraft and predetermined gross dimensions to result, after consolidation, in the finished dimensions of the composite part, • the training stage being carried out in such a way as to train at least: • a first peripheral cutout in the stack so as to define: a main portion comprising an outer edge, the first peripheral cutout being made so that the main portion has the gross dimensions, and an auxiliary portion comprising an inner edge, the auxiliary portion extending externally to the main portion with respect to the first peripheral cutout, • a second peripheral cutout in the stack so as to define: an outer edge of the auxiliary portion, and a residual portion comprising an inner edge, the residual portion extending outwardly to the auxiliary portion with respect to the second peripheral cutout, • the application step being carried out so as to apply an insulating member: • on the one hand on the inner edge of the auxiliary portion and / or on the outer edge of the main portion so that the insulating member separates the inner edge from the outer edge to prevent the mixing of the polymer resins of the main portion and the auxiliary portion, and • on the other hand on the inner edge of the residual portion and / or on the outer edge of the auxiliary portion such that the insulating member separates the inner edge of the residual portion from the outer edge of the auxiliary portion to prevent mixing of the polymer resins of the auxiliary portion and the residual portion, • the stack consolidation step being carried out so as to form each composite part directly to the finished dimensions from the main portion and the auxiliary portion, the consolidated residual portion being able to be separated from the composite parts at the level of each peripheral cut.

[0020] Such an embodiment makes it possible, for example, to form an aircraft structure in which an interior hatch is cut out while retaining the cut portion to form the access door of the hatch. This has numerous advantages in that the method allows simultaneous manufacture of the two parts, without it being necessary to carry out two stacks and two steps of consolidation by thermocompression and separation to form each part independently, which was the case in the prior art due to material losses due to the machining machine. PRESENTATION OF THE FIGURES

[0021] The invention will be better understood on reading the description which follows, given by way of example, and referring to the following figures, given by way of non-limiting examples, in which identical references are given to similar objects.

[0022] [Fig.l] is a schematic representation of a method of manufacturing a composite part according to the prior art.

[0023] [Fig.2] is a schematic representation of a wringing effect on the edges of the composite part of [Fig.l] during a polymerization step.

[0024] [Fig. 3] is a schematic representation of a step of forming a cutout of the manufacturing method according to an embodiment of the invention.

[0025] [Fig.4] is a schematic representation of a step of applying an insulating member of the manufacturing method according to an embodiment of the invention.

[0026] [Fig. 5] is a schematic representation of a juxtaposition step of the manufacturing process according to an embodiment of the invention.

[0027] [Fig.6] is a longitudinal sectional view of a main portion and an auxiliary portion after the juxtaposition step of [Fig.5].

[0028] [Fig.7] is a schematic representation of a consolidation step of the manufacturing process according to an embodiment of the invention.

[0029] [Fig.8] is a schematic representation of a separation step of the process manufacturing according to an embodiment of the invention.

[0030] [Fig.9] is a schematic representation of the step of forming a peripheral cutout for the case of the simultaneous manufacture of two composite parts according to a first embodiment of the invention.

[0031] [Fig. 10] is a schematic representation of the step of forming a peripheral cutout for the case of the simultaneous manufacture of two composite parts according to a second embodiment of the invention.

[0032] [Fig. 11] is a longitudinal sectional view of the two composite parts of [Fig. 10] during the consolidation step.

[0033] It should be noted that the figures set out the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0034] The invention relates to a method for manufacturing one or more composite parts intended to be mounted in an aircraft structure. For the sake of simplicity and clarity, the method will be described initially for the manufacture of a single composite part.

[0035] According to one aspect of the invention, the composite part is manufactured from a stack of at least one ply of a reinforcement impregnated in a polymer resin. Preferably, the stack comprises a plurality of reinforcing plies impregnated in a polymer resin. Such a stack 1 is shown in [Fig.3].

[0036] In this example, the stack 1 extends longitudinally along an X axis, laterally along a Y axis and vertically along a Z axis, so as to form an orthogonal reference frame (X, Y, Z). In the reference frame (XY, Z), the thickness of the stack 1 extends along the vertical axis Z and the horizontal plane defines the plane (X, Y).

[0037] Preferably, each ply comprises a reinforcing layer impregnated with thermoplastic or thermosetting polymer resin. More specifically, in this example, the reinforcing layer is a reinforcing fabric comprising woven carbon fibers. It goes without saying that the reinforcement could be different, for example a non-woven reinforcing film or reinforcing particles. Likewise, it goes without saying that the material of the reinforcing layer could be different, for example glass fibers, Kevlar, etc. Preferably, the thermoplastic or thermosetting polymer resin is chosen from polyepoxides (commonly referred to as “epoxy”), polyester or polyamide resins. Each ply thus forms a pre-impregnated fabric, commonly referred to as “pre-preg”.

[0038] In this example, stack 1 of several plies of pre-impregnated reinforcement is produced by draping. It goes without saying that stack 1 could alternatively be produced by a different manner known to those skilled in the art.

[0039] In practice, the PC composite part (shown in [Fig. 8]) is manufactured by thermocompression consolidation of the stack 1, the consolidation being able to be carried out by thermocompression in a heating press or in an autoclave, as will be described in more detail later. The PC composite part has finished dimensions DF, predetermined and defined in the orthogonal reference frame (X, Y, Z) to allow its assembly in the aircraft, and gross dimensions DB (shown in [Fig. 3]) predetermined to result, after consolidation, in the finished dimensions DF. Preferably, due to the shrinkage of the polymer resin during the consolidation during which the polymer resin crosslinks, the gross dimensions DB are greater than the finished dimensions DF. In particular, in this example, each gross dimension DB is greater by approximately 40x103 m respectively than each finished dimension DF.

[0040] A method of manufacturing a PC composite part from the stack 1 as described previously will now be described, with reference to FIGS. 3 to 8.

[0041] In a first step E1, with reference to [Fig. 3], an operator forms a peripheral cutout 2 in the stack 1, using a cutting tool OD. The peripheral cutout 2 makes it possible to define a main portion 3 and an auxiliary portion 4 which extends externally to the main portion 3 with respect to the peripheral cutout 2. In other words, the auxiliary portion 4 extends over the entire periphery of the main portion 3, the main portion 3 being included in the auxiliary portion 4 in the horizontal plane (X, Y). In practice, the peripheral cutout 2 is made so that the main portion 3 has the gross dimensions DB. Preferably, the peripheral cutout 2 is made manually by the operator.

[0042] The main portion 3 comprises an outer edge 31, shown in [Fig. 5] which extends over the entire periphery of the main portion 3. Similarly, the auxiliary portion 4 comprises an inner edge 41 which extends over its entire periphery. In other words, during the peripheral cutting 2, the entire inner edge 41 of the auxiliary portion 4 is positioned opposite the outer edge 31 of the main portion 3.

[0043] Preferably, the peripheral cutout 2 is made by ultrasonic cutting. Indeed, since the stack 1 comprises a raw polymer resin, it is easier to cut than a polymerized resin, which is advantageous and makes it possible to avoid the use of a heavy and bulky machining machine. In this example, the peripheral cutout 2 is made by means of an ultrasonic knife. It goes without saying that the peripheral cutout 2 could be made in a different way, for example by means of a cutter.

[0044] When the peripheral cutout 2 is completed, the main portion 3 and the auxiliary portion 4 are separated. In other words, the auxiliary portion 4 extending at the periphery of the main portion 3, when the two portions 3, 4 are separated, the inner edge 41 delimits an opening O in the stack 1, as shown in Figures 4 and 5.

[0045] In a second step E2, the operator applies an insulating member 5, in this example, to the inner edge 41 of the auxiliary portion 4, as shown in [Fig. 4]. It goes without saying that the insulating member 5 could just as easily be applied to the outer edge 31 of the main portion 3 or both to the inner edge 41 of the auxiliary portion 4 and to the outer edge 31 of the main portion 3.

[0046] Preferably, the insulating member 5 has an adhesive surface intended to be in contact with the auxiliary edge 41 and an opposite non-stick surface, insulating the main edge 31 and the auxiliary edge 41 opposite each other. In particular, preferably, the insulating member 5 is an adhesive tape, allowing simple and rapid application. In this example, the insulating member 5 is an adhesive tape of the polytetrafluoroethylene (PTFE) type, which is also resistant to the consolidation temperatures of thermoplastic or thermosetting polymers.

[0047] With reference to [Fig. 5], when the insulating member 5 is placed on the inner edge 41, the operator juxtaposes, in a third step E3, the main portion 3 and the auxiliary portion 4, so as to position opposite each other the main edge 31 of the main portion 3 and the auxiliary edge 41 of the auxiliary portion 4. In other words, in this step, the operator replaces the main portion 3 in the opening O formed in the stack 1 by the peripheral cutout 2. The insulating member 5 is then mounted between the main edge 31 and the auxiliary edge 41 and makes it possible to isolate the polymer resin of the auxiliary portion 4 from the polymer resin of the main portion 3. [Fig.6] represents a longitudinal sectional view of the main portion 3, the auxiliary portion 4 and the insulating member 5 positioned between the main edge 31 and the auxiliary edge 4L. Preferably, the main edge 31 and the auxiliary edge 41 are substantially in contact with each other, so as to ensure that the main portion 3 has the predetermined dimensions.

[0048] The stack 1, i.e. the whole of the main portion 3, the insulating member 5 and the auxiliary portion 4 is then placed in a mold M, the profile of which will give its shape to the manufactured composite part PC. The method then comprises a step of consolidation by thermocompression E4 of the stack 1, shown in [Fig.7]. During this step, the stack 1 (comprising the insulating member 5) and the mold M are put under pressure at high temperature to polymerize the polymer resin and harden the composite material in the mold M. In this example, the consolidation is carried out in an autoclave. As such, the stack 1 is, in this example, placed in the autoclave under a pressure P of between 0.1 and 0.9 MPa (between 1 and 9 bar) and heated to a temperature of between 130 and 200°C in the example of a thermoset. In the case of a thermoplastic polymer, the temperature is between 150 and 400°C. It goes without saying that the polymerization of the polymer resin could be carried out in a different way, for example by thermocompression in a press or by any process for polymerizing a composite material known to those skilled in the art.

[0049] In practice, in this step, the insulating member 5, separating the polymer resin of the main portion 3 and the polymer resin of the auxiliary portion 4, prevents the mixing of the polymer resins and allows the polymer resin of each portion 3, 4 to be polymerized separately. Thanks to the auxiliary portion 4 which extends over the entire periphery of the main portion 3, the outer edge 31 of the latter is not deformed by the pressurization. In particular, the inner edge 41 of the auxiliary portion 4 and the outer edge 31 of the main portion 3 being substantially adjacent to each other, continuity of the polymer resin is ensured in the plane and the pressurization is thus carried out uniformly and only along the vertical axis Z, as shown in [Fig.7].

[0050] When the stack 1 has cooled, the consolidated main portion 3 (i.e., whose polymer resin has crosslinked) and the consolidated auxiliary portion 4 (i.e., whose polymer resin has crosslinked) are again separated at the peripheral cutout 2, in a step E5 shown in [Fig. 8]. Thanks to the insulating member 5, the polymer resin of the main portion 3 and the polymer resin of the auxiliary portion 4 have not mixed and each portion 3, 4 has remained independent. The insulating member 5 is also removed.

[0051] The consolidated main portion 3 then has the finished dimensions DF and makes it possible to form the composite part PC directly to the predetermined dimensions. Indeed, the consolidated main portion 3 has not undergone any edge deformation, since, having no free edge, it has advantageously not been subjected to any wringing effect, the latter affecting the external free edge 42 of the auxiliary portion 4 (as shown in FIGS. 7 and 8). In other words, no machining is necessary after the separation step E5 or only very reduced machining is necessary to form the composite part PC, which allows a process that is simpler, faster and less expensive.

[0052] A method is described in which a single peripheral cutout 2 is made to delimit a single main portion 3 formed in the auxiliary portion 4. However, it goes without saying that a plurality of peripheral cutouts 2A, 2B could alternatively be formed, so as to delimit several main portions 3A, 3B, as shown in [Fig. 9]. In this embodiment, the insulating member 5 is applied to the outer edge 31 A, 31B of each main portion 3A, 3B and / or to each inner edge 41 A, 41B delimited by the different peripheral cutouts 2A, 2B. Thus, several main portions 3A, 3B can be cut to different predetermined gross dimensions DBa, Dbb, so as to simultaneously form, after consolidation, several PC composite parts directly to different predetermined finished dimensions DF. This allows a significant saving of time.

[0053] Similarly, a method is described in which only the main portion 3 makes it possible to form a composite part PC and the auxiliary portion 4 is discarded. However, in an alternative embodiment, the method makes it possible to manufacture both a first composite part from the main portion 3 and a second composite part from the auxiliary portion 4. Each of the parts has finished dimensions, predetermined and defined in the orthogonal reference frame (X, Y, Z) to allow their assembly in the aircraft, and predetermined gross dimensions DB3, DB4 to arrive, after consolidation, at the finished dimensions.

[0054] For this, with reference to [Fig. 10], the method comprises a step of forming a first peripheral cutout 21, so as to delimit the main portion 3 and the auxiliary portion 4, the auxiliary portion 4 extending peripherally outside the main portion 3, and a second peripheral cutout 22, so as to delimit the auxiliary portion 4 and a residual portion 9, the residual portion 9 extending peripherally outside the auxiliary portion 4. The first peripheral cutout 21 is made so that the main portion 3 has the first gross dimensions DB3 and the second peripheral cutout 22 is made so that the auxiliary portion 4 has the second gross dimensions DB4.

[0055] In this embodiment, the insulating member 5 is applied to the outer edge 31, 42 of the main portion 3 and of the auxiliary portion 4 and / or to the inner edge 41, 91 of the auxiliary portion 4 and of the residual portion 9, so as to insulate, on the one hand, the polymer resin of the main portion 3 and the polymer resin of the auxiliary portion 4, and, on the other hand, the polymer resin of the auxiliary portion 4 and the polymer resin of the residual portion 9.

[0056] In this embodiment, the consolidation steps E4 and separation E5 make it possible to form both a first composite part with first finished dimensions from the consolidated main portion 3, and a second composite part with second finished dimensions from the consolidated auxiliary portion 4, without any machining being necessary after polymerization of the resin. Indeed, as shown in [Fig. 11], the pressure applied during consolidation causes a wringing effect on the outer edges of the consolidated portion 4. side 9 and not on the main 3 and auxiliary 4 portions.

[0057] The method according to the invention thus makes it possible, for example, to cut a hatch in a structural panel of the aircraft, while preserving both the panel and the hatch. In the methods of the prior art, in which the stack was consolidated and then trimmed during a machining operation, the thickness of the machining cutter did not allow the two stack portions to be preserved. Also, two successive consolidation operations were necessary to reform the assembly: a first consolidation of a first stack after which the outer periphery of the hatch was trimmed and a second consolidation of a second stack after which the inner periphery of the panel was trimmed.Thanks to the process according to the invention, ultrasonic cutting before polymerization of the resin and the insulating member put in place before the consolidation step allow, after polymerization, two composite parts with the expected dimensions to be produced simultaneously.

Claims

Claims

1. Method for manufacturing at least one composite part (PC) intended to be mounted in an aircraft structure, the composite part (PC) being produced by consolidating a stack (1) of at least one ply of reinforcing fibers impregnated in a polymer resin, the composite part (PC) having predetermined finished dimensions (DF) to allow its mounting in the aircraft, gross dimensions (DB) of the composite part (PC) being predetermined to result, after consolidation, in the finished dimensions (DF) of the composite part (PC), the method comprising: • a step of forming (El) at least one peripheral cutout (2) in the stack (1) so as to define: • at least one main portion (3) comprising an outer edge (31), the peripheral cutout (2) being made so that the main portion (3) has the gross dimensions (DB), • an auxiliary portion (4) comprising an inner edge (41), the auxiliary portion (4) extending externally to the main portion (3) with respect to the peripheral cutout (2), • a step (E2) of applying at least one insulating member (5) to the inner edge (41) of the auxiliary portion (4) and / or to the outer edge (31) of the main portion (3) so that the insulating member (5) separates the inner edge (41) and the outer edge (31) to prevent the mixing of the polymer resins of the main portion (3) and the auxiliary portion (4), and • a consolidation step (E4) by thermocompression of the stack (1) so as to form the composite part (PC) directly to the finished dimensions (DF) from the main portion (3), the consolidated auxiliary portion (4) being able to be separated from the composite part (PC) at the peripheral cutout (2).

2. Manufacturing method according to claim 1, the method being free from a step of machining the composite part (PC) after separation of the composite part (PC) and the consolidated auxiliary portion (4).

3. Manufacturing method according to one of claims 1 to 2, in which the insulating member (5) has an adhesive surface intended to be in contact with the main edge (31) or the auxiliary edge (41) and an opposite non-adhesive surface.

4. A manufacturing method according to claim 3, wherein the insulating member (5) is a polytetrafluoroethylene (PTFE) type adhesive tape.

5. Manufacturing method according to one of claims 1 to 4, in which the peripheral cut (2) is carried out by ultrasonic cutting.

6. Manufacturing method according to one of claims 1 to 5, the method being configured to manufacture a plurality of composite parts (PC) intended to be mounted in an aircraft structure and each having predetermined finished dimensions (DF) to allow its mounting in the aircraft and predetermined gross dimensions (DBA, Dbb) to result, after consolidation, in the finished dimensions (DF) of the composite part (PC), the forming step (El) is carried out so as to form a plurality of peripheral cutouts (2A, 2B) in the stack (1) so as to define: • a plurality of main portions (3A, 3B) each comprising an outer edge (31A, 31B), each peripheral cutout (2A, 2B) being produced so that each main portion (3A, 3B) has the gross dimensions (DBA, DBB), • an auxiliary portion (4) comprising a plurality of inner edges (41A, 41B),the auxiliary portion (4) extending externally to each main portion (3A, 3B) with respect to each peripheral cutout (2A, 2B), • the step of applying (E2) at least one insulating member (5) being carried out on each inner edge (41 A, 41B) of the auxiliary portion (4A, 4B) and / or on each outer edge (31 A, 31B) of each main portion (3A, 3B) so that the insulating member (5) separates the inner edges (41 A, 41B) respectively from the outer edges (31 A, 31B) to prevent the mixing of the polymer resins of each main portion (3A, 3B) and of the auxiliary portion (4), and • the step of consolidating (E4) the stack (1) being,

7. produced in such a way as to form each composite part (PC) directly to the finished dimensions (DF) from each main portion (3A, 3B), the consolidated auxiliary portion (4) being capable of being separated from the composite parts (PC) at the level of each peripheral cut (2A, 2B). Manufacturing method according to one of claims 1 to 6, the method being configured to manufacture a plurality of composite parts (PC) intended to be mounted in an aircraft structure and each having predetermined finished dimensions (DF) to allow its mounting in the aircraft and predetermined gross dimensions (DB3, DB4) to result, after consolidation, in the finished dimensions (DF) of the composite part (PC), • the training step (El) being carried out in such a way as to form at least: • a first peripheral cutout (21) in the stack (1) so as to define: a main portion (3) comprising an outer edge (31), the first peripheral cutout (21) being made so that the main portion (3) has the gross dimensions (DB3), and an auxiliary portion (4) comprising an inner edge (41), the auxiliary portion (4) extending externally to the main portion (3) with respect to the first peripheral cutout (21), • a second peripheral cutout (22) in the stack (1) so as to define: an outer edge (42) of the auxiliary portion (4), and a residual portion (9) comprising an inner edge (91), the residual portion (9) extending externally to the auxiliary portion (4) with respect to the second peripheral cutout (22), • the application step (E2) being carried out so as to apply an insulating member (5): • on the one hand on the inner edge (41) of the auxiliary portion (4) and / or on the outer edge (31) of the main portion (3) so that the member insulator (5) separates the inner edge (41) from the outer edge (31) to prevent mixing of the polymer resins of the main portion (3) and the auxiliary portion (4), and • on the other hand on the inner edge (91) of the residual portion (9) and / or on the outer edge (42) of the auxiliary portion (4) so that the insulating member (5) separates the inner edge (91) of the residual portion (9) from the outer edge (42) of the auxiliary portion (4) to prevent the mixing of the polymer resins of the auxiliary portion (4) and the residual portion (9) the consolidation step (E4) of the stack (1) being carried out so as to form each composite part (PC) directly to the finished dimensions (DF) from the main portion (3) and the auxiliary portion (4), the consolidated residual portion (9) being capable of being separated from the composite parts (PC) at each peripheral cutout (21, 22).

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