Manufacturing process for a composite part

Abstract

A method for manufacturing at least one composite part intended for mounting 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 an auxiliary portion (4) extending externally from the main portion (3) with respect to the peripheral cutout (2); a step of applying at least one insulating element (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) the stack by thermocompression 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 to 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 a composite material, a reinforcing fabric (for example, a woven carbon fiber reinforcement) is impregnated with thermoplastic or thermosetting polymer resin to form a prepreg fabric, commonly referred to as a "pre-preg." A stack of several prepreg fabrics is then created 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], which represents a side view of the EMP stack, the pressure P applied during polymerization causes a deformation Q to appear on the edges of the EMP stack. Such a deformation Q is known to those skilled in the art as the "spin effect" and can affect the mechanical performance of the composite part manufactured.

[0004] Therefore, to overcome this drawback, as shown in [Fig. 1], current processes involve first manufacturing a rough part EB, whose dimensions DB are larger than the dimensions DF of the finished part F. After polymerization, the rough part EB is machined and trimmed to remove the deformed portion Q and form the finished part 1 with the expected dimensions DF and clean edges. In a known manner, to perform 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 unwanted movement under the effect of the machining pressure. The clamped rough part EB is then machined to remove the edges that have been subjected to the vacuum effect.

[0005] However, such a process has many drawbacks. Indeed, the machining process is long and tedious and significantly increases manufacturing lead times. Moreover, machining requires heavy, bulky, and complex tooling to hold the workpiece in place. Furthermore, the tooling must be specifically adapted The machining process is specific to the part being machined, particularly the flow channels beneath it to create the vacuum. Furthermore, it is necessary to create multiple tooling sets to accommodate different parts, which is complex and time-consuming. Machining machines also have the disadvantage of being energy-intensive and requiring various consumables such as lubricants, thus increasing costs. Finally, machining is generally performed using a CNC machine. This necessitates creating a machining program for each part, which is again a lengthy and tedious process.

[0006] The invention thus aims to eliminate at least some of these drawbacks by proposing a fast and efficient method for manufacturing a composite part for an aircraft. The method according to the invention aims in particular to eliminate the need for an initial 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 for mounting in an aircraft structure, the composite part being made 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, with predetermined rough dimensions of the composite part resulting, after consolidation, in the finished dimensions of the composite part. The method comprises: • a step of forming at least one peripheral cut in the stack so as to define: • at least one main portion including an outer border, the peripheral cut being made in such a way that the main portion has the gross dimensions, • an auxiliary portion comprising an inner border, the auxiliary portion extending externally from the main portion with respect to the peripheral cutout, • a step of applying at least one insulating element to the inner edge of the auxiliary portion and / or to the outer edge of the main portion in such a way that the insulating element separates the inner and outer edges to prevent the mixing of the polymer resins of the main and auxiliary portions, and • a thermocompression consolidation step of the stack to form the composite part directly to the finished dimensions from the main portion, the consolidated auxiliary portion being suitable for being separated from the composite part at the level of the peripheral cut.

[0008] The manufacturing process according to the invention advantageously allows the composite part to be manufactured to the finished dimensions directly after the consolidation step, simply by separating the consolidated main portion from the consolidated auxiliary portion, without the need for trimming the stack whose 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 heated press.

[0010] The insulating element applied and positioned at the peripheral cut between the main portion and the auxiliary portion advantageously prevents the polymer resins of each portion from mixing and crystallizing together during the consolidation operation. This allows each portion to be polymerized independently and then separated quickly and easily, without the need for any special tooling.

[0011] Peripheral cutting before curing the polymer resin is simpler and faster to perform, since it is not necessary to clamp the stack onto specific tooling. The process according to the invention thus allows for significant time savings. Furthermore, it is not necessary to manufacture special tooling for each composite part to be produced, which is particularly advantageous and allows for a significant reduction in production costs.

[0012] Furthermore, eliminating the need for machining after consolidation avoids the formation of a rough part with dimensions larger than the finished dimensions of the composite part, thus allowing for subsequent trimming to the correct dimensions. This significantly reduces the amount of material required to manufacture the composite part. Cutting the stack before consolidation also allows for a precise cut (unlike a milling cutter used for machining), thereby minimizing material waste or the discarding of portions damaged by machining.

[0013] Preferably, the manufacturing process eliminates the need for a machining step on the composite part after the separation of the composite part from the consolidated auxiliary portion, resulting in time savings and cost reductions. This eliminates the need for manufacturing, storing, and managing different tooling for each composite part to be produced, while also reducing energy consumption (particularly significant for a machining center) and eliminating the need to create a machining program for each part, which is a lengthy and tedious process.

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

[0015] Preferably, the insulating element is a polytetrafluoroethylene adhesive tape. Such an adhesive tape, known by the acronym "PTFE", advantageously allows for the effective insulation of the main and auxiliary portions while possessing mechanical characteristics capable of withstanding the temperatures and pressures experienced during the consolidation stage.

[0016] Preferably, the peripheral cutting is performed by ultrasonic cutting. Ultrasound allows for a fine cut that does not affect the predetermined dimensions of the composite part. Indeed, since the stack comprises a raw or "raw" polymer resin, i.e., unpolymerized, the resin is more flexible and easier to cut. Thus, it is advantageously unnecessary to use, for example, a machining center with a milling cutter to perform contouring, as was the case in the prior art. Ultrasonic cutting can easily be performed manually by an operator.

[0017] In one embodiment, the process being configured to manufacture a plurality of composite parts intended to be mounted in an aircraft structure and each having predetermined finite dimensions to allow its mounting in the aircraft and predetermined gross dimensions to result, after consolidation, in the finite 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 principal portions, each comprising an outer border, each peripheral cut being made so that each principal portion has the gross dimensions, • an auxiliary portion comprising a plurality of internal borders, the auxiliary portion extending externally from each main portion opposite each peripheral cutout, • the step of applying at least one insulating element being carried out on each inner edge of the auxiliary portion and / or on each outer edge of each main portion in such a way that the insulating element separates the inner edges respectively from the outer edges to prevent the a mixture of polymer resins from each main portion and the auxiliary portion, and • the stack consolidation step being carried out in such a way 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 process thus makes it possible to manufacture several composite parts in a single stack from several main portions cut from the stack and each separated from the auxiliary portion by an insulating element, which represents a significant time saving. Since the peripheral cutting is carried out before consolidation and is therefore finer, it allows for the formation of a larger number of main parts in the same stack, thereby reducing both production time and costs.

[0019] In one embodiment, the process being configured to manufacture a plurality of composite parts intended to be mounted in an aircraft structure and each having predetermined finite dimensions to allow its assembly in the aircraft and predetermined gross dimensions to result, after consolidation, in the finite dimensions of the composite part, • the training stage being carried out in such a way as to train at least: • a first peripheral cut in the stack so as to define: a main portion including an outer edge, the first peripheral cut being made so that the main portion has the gross dimensions, and an auxiliary portion including an inner edge, the auxiliary portion extending outwards from the main portion with respect to the first peripheral cut, • a second peripheral cut in the stack so as to define: an outer edge of the auxiliary portion, and a residual portion including an inner edge, the residual portion extending outwards from the auxiliary portion with respect to the second peripheral cut, • the application step being carried out in such a way as to apply an insulating element: • 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 element 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 so that the insulating element separates the inner edge of the residual portion from the outer edge of the auxiliary portion to prevent the mixing of the polymer resins of the auxiliary portion and the residual portion, • the stack consolidation step being carried out in such a way 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 internal hatch is cut out while retaining the cut-out portion to form the hatch's access door. This offers numerous advantages in that the process allows for the simultaneous manufacture of both parts, without the need for two stacking steps and two thermocompression consolidation and separation steps to form each part independently, as was the case in the prior art due to material losses caused by the machining process. PRESENTATION OF FIGURES

[0021] The invention will be better understood upon reading the following description, 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. 1 is a schematic representation of a process for 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. 1 during a polymerization step.

[0024] Fig. 3 is a schematic representation of a cutting formation step in the manufacturing process according to one embodiment of the invention.

[0025] Fig. 4 is a schematic representation of a step in the application of an insulating element of the manufacturing process according to an embodiment of the invention.

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

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

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

[0029] Figure 8 is a schematic representation of a separation step in the process manufacturing according to a method of implementing the invention.

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

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

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

[0033] It should be noted that the figures set out the invention in detail to implement the invention, said figures being of course able to serve 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 initially be described for the manufacture of a single composite part.

[0035] According to one aspect of the invention, the composite part is made from a stack of at least one ply of a reinforcement impregnated in a polymer resin. Preferably, the stack comprises a plurality of reinforcement 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 coordinate system (X, Y, Z). In the (XY, Z) coordinate system, the thickness of the stack 1 extends along the vertical Z-axis, and the horizontal plane defines the (X, Y) plane.

[0037] Preferably, each ply comprises a reinforcing layer impregnated with a thermoplastic or thermosetting polymer resin. More specifically, in this example, the reinforcing layer is a reinforcing fabric comprising woven carbon fibers. It is understood that the reinforcement could be different, for example, a non-woven reinforcing film or reinforcing particles. Similarly, it is understood that the material of the reinforcing layer could be different, for example, glass fibers, Kevlar, etc. Preferably, the thermoplastic or thermosetting polymer resin is selected from polyepoxides (commonly referred to as "epoxy"), polyester resins, or polyamide resins. Each ply thus forms a pre-impregnated fabric, commonly referred to as "pre-preg."

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

[0039] In practice, the composite PC part (shown in [Fig. 8]) is manufactured by thermocompression consolidation of the stack 1. This consolidation can be carried out by thermocompression in a heated press or in an autoclave, as will be described in more detail later. The composite PC part has predetermined finite dimensions DF, defined in the orthogonal coordinate system (X, Y, Z) to allow its assembly in the aircraft, and predetermined rough dimensions DB (shown in [Fig. 3]) that result, after consolidation, in the finite dimensions DF. Preferably, due to the shrinkage of the polymer resin during consolidation, during which the polymer resin crosslinks, the rough dimensions DB are larger than the finite dimensions DF. In particular, in this example, each rough dimension DB is approximately 40 x 10³ m larger than each finite dimension DF.

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

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

[0042] The main portion 3 includes an outer edge 31, shown in [Fig. 5], which extends around the entire periphery of the main portion 3. Similarly, the auxiliary portion 4 has an inner edge 41 that extends around its entire periphery. In other words, during the peripheral cut 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 cut 2 is made by ultrasonic cutting. Since the stack 1 comprises a raw polymer resin, it is easier to cut than a polymerized resin, which is advantageous and eliminates the need for a heavy and bulky machining center. In this example, the peripheral cut 2 is made using an ultrasonic cutter. It goes without saying that the peripheral cut 2 could be made differently, for example, using a utility knife.

[0044] When the peripheral cut 2 is completed, the main portion 3 and the auxiliary portion 4 are separated. In other words, the auxiliary portion 4 extending around the periphery of the main portion 3, when the two portions 3 and 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 element 5, in this example, to the inner edge 41 of the auxiliary portion 4, as shown in [Fig. 4]. It is understood that the insulating element 5 could just as easily be applied to the outer edge 31 of the main portion 3 or to both the inner edge 41 of the auxiliary portion 4 and the outer edge 31 of the main portion 3.

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

[0047] With reference to [Fig. 5], when the insulating element 5 is placed on the inner edge 41, the operator, in a third step E3, juxtaposes the main portion 3 and the auxiliary portion 4, so as to position the main edge 31 of the main portion 3 and the auxiliary edge 41 of the auxiliary portion 4 opposite each other. 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 cut 2. The insulating element 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.Figure 6] represents a longitudinal cross-sectional view of the main portion 3, the auxiliary portion 4 and the insulating element 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 assembly of the main portion 3, the insulating element 5, and the auxiliary portion 4, is then placed in a mold M, the profile of which will give shape to the composite part PC. The process then includes a thermocompression consolidation step E4 of the stack 1, shown in [Fig. 7]. During this step, the stack 1 (including the insulating element 5) and the mold M are subjected to high-temperature pressure 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 is placed under a pressure P between 0.1 and 0.9 MPa (between 1 and 9 bar) and heated to a temperature between 130 and 200 °C in the case of a thermosetting resin. For a thermoplastic polymer, the temperature is between 150 and 400 °C. It goes without saying that the polymerization of the resin could be carried out differently, for example by thermocompression in a press or by any polymerization process for a composite material known to those skilled in the art.

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

[0050] When the stack 1 has cooled, the consolidated main portion 3 (i.e., the portion in which the polymer resin has crosslinked) and the consolidated auxiliary portion 4 (i.e., the portion in which the polymer resin has crosslinked) are separated again at the peripheral cut 2, in a step E5 shown in [Fig. 8]. Thanks to the insulating element 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 element 5 is also removed.

[0051] The consolidated main portion 3 then has the finished dimensions DF and allows the composite part PC to be formed 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 outer free edge 42 of the auxiliary portion 4 (as shown in Figures 7 and 8). In other words, no machining is necessary after the separation step E5, or only very minimal machining is required to form the composite part PC, which allows for a process that is simpler, faster, and less expensive.

[0052] A method is described in which a single peripheral cut 2 is made to delimit a single main portion 3 formed in the auxiliary portion 4. However, it is understood that a plurality of peripheral cuts 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 element 5 is applied to the outer edge 31A, 31B of each main portion 3A, 3B and / or to each inner edge 41A, 41B delimited by the various peripheral cutouts 2A, 2B. Thus, several main portions 3A, 3B can be cut to different predetermined rough dimensions DBa, Dbb, so as to simultaneously form, after consolidation, several composite PC parts directly to different predetermined finished dimensions DF. This allows for significant time savings.

[0053] Similarly, a process is described in which only the main portion 3 is used to form a composite part PC, and the auxiliary portion 4 is discarded. However, in an alternative embodiment, the process 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 finite dimensions, predetermined and defined in the orthogonal coordinate system (X, Y, Z) to allow their assembly in the aircraft, and predetermined rough dimensions DB3, DB4 which, after consolidation, result in the finite dimensions.

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

[0055] In this embodiment, the insulating element 5 is applied to the outer edge 31, 42 of the main portion 3 and the auxiliary portion 4 and / or to the inner edge 41, 91 of the auxiliary portion 4 and the residual portion 9, so as to isolate, 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 steps E5 make it possible to form both a first composite part with first finite dimensions from the consolidated main portion 3, and a second composite part with second finite 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. side 9 and not on the main portions 3 and auxiliary 4.

[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 prior art methods, in which the stack was consolidated and then trimmed during a machining operation, the thickness of the milling cutter did not allow the two stack portions to be preserved. Therefore, two successive consolidation operations were necessary to recreate 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 element put in place before the consolidation stage allow after polymerization to simultaneously produce two composite parts of the expected dimensions.

Claims

Demands

1. A method for manufacturing at least one composite part (PC) intended for mounting 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, with predetermined gross dimensions (DB) of the composite part (PC) resulting, after consolidation, in the finished dimensions (DF) of the composite part (PC), the method comprising: • a forming step (El) of at least one peripheral cut (2) in the stack (1) so as to define: • at least one main portion (3) comprising an outer edge (31), the peripheral cut (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 outwards from the main portion (3) with respect to the peripheral cut (2), • an application step (E2) of at least one insulating element (5) 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 insulating element (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 level of the peripheral cut (2).

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

3. A manufacturing method according to any one of claims 1 to 2, wherein the insulating element (5) has an adhesive surface intended to be in contact with the main edge (31) or the auxiliary edge (41) and an opposing non-stick surface.

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

5. A manufacturing method according to any one of claims 1 to 4, wherein the peripheral cutting (2) is carried out by ultrasonic cutting.

6. A manufacturing method according to any one of claims 1 to 5, the method being configured to manufacture a plurality of composite parts (CPs) intended to be mounted in an aircraft structure and each having predetermined finished dimensions (FD) to allow its mounting in the aircraft and predetermined rough dimensions (DBA, Dbb) to result, after consolidation, in the finished dimensions (FD) of the composite part (CP), the forming step (E1) 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 made so that each main portion (3A, 3B) has the rough dimensions (DBA, DBB), • an auxiliary portion (4) comprising a plurality of inner edges (41A, 41B),the auxiliary portion (4) extending externally from each main portion (3A, 3B) opposite each peripheral cutout (2A, 2B), • the application step (E2) of at least one insulating element (5) being carried out on each inner edge (41A, 41B) of the auxiliary portion (4A, 4B) and / or on each outer edge (31A, 31B) of each main portion (3A, 3B) so that the insulating element (5) separates the inner edges (41A, 41B) respectively from the outer edges (31A, 31B) to prevent the mixing of the polymer resins of each main portion (3A, 3B) and the auxiliary portion (4), and • the consolidation step (E4) of the stack (1) being,

7. made so 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 able to be separated from the composite parts (PC) at the level of each peripheral cut (2A, 2B). A manufacturing method according to any 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 rough 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 train at least: • a first peripheral cut (21) in the stack (1) so as to define: a main portion (3) comprising an outer border (31), the first peripheral cut (21) being made so that the main portion (3) has the gross dimensions (DB3), and an auxiliary portion (4) comprising an inner border (41), the auxiliary portion (4) extending outwards from the main portion (3) with respect to the first peripheral cut (21), • a second peripheral cut (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 outwards from the auxiliary portion (4) with respect to the second peripheral cut (22), • the application step (E2) being carried out in such a way as to apply an insulating element (5): • on the one hand on the inner border (41) of the auxiliary portion (4) and / or on the outer border (31) of the main portion (3) so that the organ insulating material (5) separates the inner edge (41) from the outer edge (31) to prevent the 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 element (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 able to be separated from the composite parts (PC) at the level of each peripheral cut (21, 22).