Manufacturing process of a composite part

Abstract

The invention relates to a method for manufacturing a composite part, said method comprising the following successive steps: (i) Manufacturing an elongated textile preform that is not consolidated using a specific device, (ii) Consolidation of the textile preform obtained in the previous step, comprising: - a heating step in a closed mold at a temperature higher than the melting temperature of the thermoplastic matrix and under pressure, the mold (43) imposing a change of shape on the preform, then - a cooling step within the mold of the consolidated preform (iii) Demolding the composite part at a temperature lower than the crystallization temperature of the thermoplastic matrix. Figure for the abstract: Fig. 8

Description

Title of the invention: Method for manufacturing a composite part Field of invention

[0001] The invention relates to a method of manufacturing a composite part and to this composite part. Technical background

[0002] The processes conventionally used to manufacture composite parts based on reinforcing fibers and thermosetting or thermoplastic resins are numerous: infusion, injection, extrusion, pultrusion, powder coating, thermocompression, stamping, etc. There are also robotic processes of the AFP or filament winding type, which make it possible to produce composite parts either directly from raw materials mixed in line (fiber and resin), or from semi-finished products. The semi-finished products usable in AFP and filament winding, comprising thermoplastic resins, can be thermoplastic prepregs.

[0003] Other innovative technologies make it possible to produce composite parts from prepregs (thermoplastic or thermosetting), most of which are inspired by the textile industries. Examples include weaving or braiding, which generate 2D or 3D shapes that can be used to manufacture composite parts after assembling different individual composite elements.

[0004] The manufacturing processes for composite parts having an axis of revolution, existing industrially such as wet filament winding, by winding thermoplastic composite ribbons for example, are generally slow; either because of the long time required for the deposition of the prepregs; or (or in addition) because of the polymerization times (cooking) required for the polymerization of thermosetting resins for example.

[0005] Furthermore, the heating processes are generally not optimized, neither technically (LASER which tends to overheat thermoplastic composites for example), nor economically (cooking time of several hours for thermoset composites in an oven or autoclave, therefore with high energy consumption in electricity and inert gas).

[0006] The quality of the composites obtained is often imperfect, due to the presence of porosities, linked to the low pressure applied during the implementation of the fibers pre-impregnated with resin, when it comes to wet impregnation or during the in situ consolidation of the thermoplastic composite ribbons.

[0007] In addition, and this is mainly the case for manual removal processes but also for robotic processes, there is a potentially significant loss of raw material. during manufacturing. For example, there are minimum dimensions that can be deposited using the AFP or filament winding process. There are also significant minimum lengths required (several meters or even tens of meters / reel) to reach the depositing head from the reel (or creel), as this material is not actually used in the final part.

[0008] Finally, conventional manufacturing processes do not allow certain prepreg deposition geometries to be achieved either because of the excessive bulk of the processing equipment (dimensions of the AFP deposition head for example) or because of the deposition angles which are physically not achievable without over-consuming material in the external zones of the tubular parts.

[0009] In the textile field, document WO2023 / 089051 discloses a method for manufacturing an unconsolidated elongated textile element.

[0010] The problem to be solved is to find an efficient manufacturing process, both technically (in particular in terms of mechanical performance) and economically (manufacturing cycle time, losses of materials or energy linked to the manufacturing or assembly process, etc.), to manufacture complex-shaped parts with improved mechanical strength. These parts thus manufactured can then be used / assembled to manufacture a composite 3D object optimized in its design and performance as well as from an economic point of view.

[0011] For the purposes of the present invention, a complex shape means a part which may have different angles, and / or at least one non-planar surface, and / or variations in the internal distances of the hollow parts, and / or changes in the shapes of the sections in a hollow part.

[0012] A major advantage of the process is its productivity linked to the continuous manufacturing of the preform of the parts at a significant speed (typically 0.5 to Im / min in longitudinal tube production speed) as well as to the consolidation in a closed mold (either fast or in parallel with several molds).

[0013] Another advantage is the quality of consolidation of the final composite part thanks to the use of a closed mold under pressure. The closed mold also offers the advantage of low or even no degradation by thermo-oxidation of the resin making up the matrix of the composite, which will be particularly valuable when using a polyamide (PA) matrix for the composite.

[0014] Consequently, a simple, rapid and inexpensive process is currently being sought which makes it possible to obtain composite parts of complex shape which have good mechanical strength, in particular at high temperature, and which are recyclable.

[0015] Today, complex-shaped composite parts with good mechanical strength, particularly at high temperatures, and which are recyclable, are sought after. Summary of the invention

[0016] This problem is solved by the method of the invention which comprises at least three steps: - A first step i) of manufacturing an elongated and unconsolidated textile preform, comprising several layers of thermoplastic composite ribbons, each layer comprising a ribbon wound at a given angle, without embedding, said preform being capable of being obtained from a specific device, represented in [Fig.l]; - A second consolidation step ii) of the textile preform obtained in the previous step in a complex-shaped mold; - A third step iii) of demolding.

[0017] This process has many advantages.

[0018] First of all, unlike processes involving braiding or weaving and which require going over the same layer to stack several layers of woven or braided ribbons, the manufacture of the preform according to step i) of the process of the invention can be carried out continuously, and therefore allows rapid and inexpensive access to textile preforms of large dimensions, in particular of small diameter with great lengths.

[0019] Furthermore, step i) of the method according to the invention makes it possible to superimpose a very large number of layers: the preform can contain as many desired layers of tape as there are modules used.

[0020] The device implemented in step i) uses guides to deploy the ribbons in the same direction. It thus makes it possible to produce elongated textile preforms of different shapes, cylindrical or not. The preform obtained according to step i) may also include section restrictions, at which certain ribbons may be cut and welded, and inserts positioned, in particular before consolidation. Similarly, the preform can be easily bent at room temperature in order to give it a particular non-rectilinear shape which is then fixed during the consolidation step ii). This will however require a particular choice of the fiber orientations in the different layers of the preform.

[0021] Step ii) of consolidation in a mold of complex shape makes it possible to consolidate the preform, while giving it a specific shape. Step ii) will thus consolidate the preform by melting the thermoplastic matrix and will deform this preform. During the melting of the preform, it will deform to the shape of the chosen mold.

[0022] This step thus makes it possible to achieve complex shapes, without the final part losing mechanical resistance.

[0023] Advantageously, step ii) can allow co-consolidation, within a single and at the same stage, thermoplastic or metallic inserts, with the ribbons of the textile preform, allowing in particular to adapt the composite part obtained to other elements. In addition, this co-consolidation makes it possible to improve the mechanical resistance and / or the cohesion between the insert and the co-consolidated composite part.

[0024] The method includes a step iii) of demolding, which must be carried out at a specific temperature so as not to damage the structure and shape of the final part obtained.

[0025] The invention thus relates, according to a first aspect, to a method of manufacturing a composite part, said method comprising the following successive steps:

[0026] (i) Manufacture of an elongated textile and unconsolidated preform by means of a device (1) comprising: - a frame (2) comprising a main longitudinal guide (3) in a direction X, said guide (3) being fixed on the frame (2) and - at least two modules (4) arranged in series around the guide (3) in the X direction, each module (4) comprising: - a feed crown (5) surrounding a section of the guide (3), - feed means (6) arranged on the crown (5) capable of feeding at least one ribbon (10) towards the guide (3) at a winding angle of between -90° and 90° with the direction X and at a feed speed VI, each ribbon (10) being capable of winding at least around the guide (3) or on the upper layer of ribbon (10), and - drive means (15) for the crown (5) capable of rotating the crown (5) around the guide (3) at a rotation speed V2, Said preform being manufactured according to a process comprising the steps of: Implementation of the supply means (6) on each of the modules (4), said supply means (6) comprising selected ribbons (10), said selected ribbons (10) comprising at least thermoplastic composite ribbons Setting the feed speed VI and the rotation speed V2 of each of the modules (4) and starting up each module (4), Cutting of the elongated element (11) and / or exhaustion of the ribbons (10), and Recovery of the unconsolidated elongated textile preform (11) obtained; (ii) Consolidation of the textile preform obtained in the previous step, comprising: - a heating step in a closed mold (43) at a temperature higher than the melting temperature of the thermoplastic matrix and under pressure, the mold (43) imposing a change of shape on the preform, then - a cooling step within the mold (43) of the consolidated preform, (III) Demolding of the composite part at a temperature lower than the crystallization temperature of the thermoplastic matrix.

[0027] In embodiments, the method according to the invention comprises one or more of the following additional features: - the heating step of step ii) is carried out at a temperature between a temperature equal to the melting temperature of the thermoplastic matrix + 5°C and the melting temperature of the thermoplastic matrix + 80°C, more particularly between a temperature equal to the melting temperature of the thermoplastic matrix + 10°C and the melting temperature of the thermoplastic matrix + 60°C. - the heating step of step ii) is carried out at a pressure of between 0.5 bar and 50 bar, in particular between 0.5 bar and 10 bar, in particular between 0.5 bar and 7 bar, in particular between 1 and 7 bar. - consolidation step ii) uses a bladder placed in the preform and applying internal pressure. - a bending step is carried out before the consolidation step ii). - thermoplastic composite tapes include: • Reinforcing fibers, continuous or discontinuous, of an inorganic or natural material; and • A composition of thermoplastic polymers. - the reinforcing fibers of an inorganic or natural material are: • impregnated or pre-impregnated with a composition of thermoplastic polymers, or • mixed with thermoplastic polymer fibers. - the thermoplastic polymer composition of the composite tape mainly comprises at least one thermoplastic polymer selected from: polyaryl ether ketones (PAEK), in particular poly(ether ether ketone) (PEEK); polyaryl ether ketone ketone (PAEKK), in particular poly(ether ketone ketone) (PEKK); polyaryl sulfones; polyaryl sulfides, in particular polyphenylene sulfides (PPS); polyamides (PA), in particular semi-aromatic polyamides (polyphthalamides) optionally modified with urea units; PEBA, polyolefins, in particular polypropylene, polylactic acid (PLA), polyvinyl alcohol (PVA), and fluorinated polymers, in particular polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE) or polychlorotrifluoroethylene (PCTFE); and their mixtures, preferably, the thermoplastic polymer composition of the composite tape mainly comprises a polyamide, preferably semi-crystalline. - the thermoplastic polymer is an aliphatic, cycloaliphatic or semi-aromatic polyamide. - the fibers of the thermoplastic composite ribbons are chosen from glass fibers, carbon fibers, basalt or basalt-based fibers or are natural fibers such as flax fibers, reinforcements or bamboo fibers or hemp or cellulose fibers. - the fibers of thermoplastic composite ribbons are unidirectional, i.e. all oriented along the length of the ribbon. - the composite tapes contain a fiber content of between 40 and 70% by volume, preferably between 50 and 60% by volume of the thermoplastic composite tapes. - the selected ribbons (10) further comprise non-composite ribbons (10) of thermoplastic polymer. - the non-composite thermoplastic polymer ribbons (10) represent a minority mass fraction of the preform compared to the mass fraction of the thermoplastic composite ribbons. - the ribbons (10) have a thickness of between 50 and 300 pm, in particular between 50 and 260 pm and more particularly between 60 pm and 170 pm. - the ribbons (10) have a width of between 5 mm and 50 mm, in particular between 10 mm and 15 mm. - the winding angle of the ribbon (10) relative to the X direction is between +90° and - 90°.

[0028] According to a second aspect, the invention relates to a composite part capable of being obtained according to the method of the invention.

[0029] According to a third aspect, the invention relates to the use of the composite part in the field of sport, in particular as an element of a sporting article, preferably a bicycle frame, a racket frame, a ski pole, a hiking pole, a hockey stick, a golf club, a canoe or kayak oar.

[0030] The inventors were able to show that the composite parts obtained according to the process of the invention exhibited very good mechanical resistance compared to the composite parts of the state of the art.

[0031] Indeed, unlike conventional methods involving braiding of composite ribbons, the method of the invention preferably allows winding of the ribbons without weaving, which makes it possible to avoid local overstressing at the points where the fibers cross each other, and therefore to improve the mechanical strength of the elongated textile element obtained after consolidation, i.e. of the composite part.

[0032] Advantageously, the consolidation step ii) can be carried out under pressure, in particular under a pressure of between 5 and 10 bars, which makes it possible both to further improve the mechanical resistance and to reduce the porosity of the material. composite.

[0033] Indeed, conventional processes using wet filament winding or winding of thermoplastic composite ribbons do not allow high pressure to be applied, particularly for a prolonged period, so that the quality of the consolidation is often quite low.

[0034] Furthermore, the inventors were able to observe that step ii) of consolidation of the preform under pressure made it possible to give the composite part obtained a very low residual porosity, in particular less than 10%, less than 5%, in particular less than 2%.

[0035] Advantageously, the step of consolidating the preform in a closed mold also makes it possible to reduce the thermo-oxidation of the resin which occurs during the deposition of thermoplastic tape in the open air, and thus to contribute to the improvement of the mechanical properties of the composite tubular structure thus obtained. Brief description of the figures

[0036] [Fig. 1] is a perspective view of an example of a device used in step i) of the method according to the invention,

[0037] [Fig.2] is a perspective view from an opposite angle of [Fig.l] of the device used in step i) of the method,

[0038] [Fig.3] is a perspective view of an example of a device module used in step i) of the method according to the invention,

[0039] [Fig.4] is a perspective view of the module of [Fig.3],

[0040] [Fig.5] is a perspective view of an exemplary ribbon feeding means according to the invention,

[0041] [Fig.6] is a perspective view of another exemplary embodiment of a device used in step i) of the method according to the invention,

[0042] [Fig.7] is a perspective view from an opposite angle of the device of [Fig.6],

[0043] [Fig.8] is a diagram representing the implementation of the method according to the invention,

[0044] [Fig.9] is a perspective view of the final composite part.

[0045] It should be noted that in these figures, the common structural and / or functional elements different variants may have the same references. Detailed description

[0046] The invention is now described in more detail and in a non-limiting manner in the following description.

[0047] Unless otherwise indicated, all percentages relating to quantities are volume percentages. Manufacturing process of a composite part

[0048] According to a first aspect, the invention relates to a method of manufacturing a part elongated and consolidated textile, said method comprising the following successive steps: (i) Manufacture of an elongated, unconsolidated textile preform using a device (1) comprising:

[0049] - a frame (2) comprising a main longitudinal guide (3) in a direction X, said guide (3) being fixed on the frame (2) and - at least two modules (4) arranged in series around the guide (3) in the X direction, each module (4) comprising: - a feed crown (5) surrounding a section of the guide (3), - feed means (6) arranged on the crown (5) capable of feeding at least one ribbon (10) towards the guide (3) at a winding angle of between -90° and 90° with the direction X and at a feed speed VI, each ribbon (10) being capable of winding at least around the guide (3) or on the upper layer of ribbon (10), and - drive means (15) for the crown (5) capable of rotating the crown (5) around the guide (3) at a rotation speed V2, Said preform being manufactured according to a process comprising the steps of: Implementation of the supply means (6) on each of the modules (4), said supply means (6) comprising selected ribbons (10), said selected ribbons (10) comprising thermoplastic composite ribbons, Setting the feed speed VI and the rotation speed V2 of each of the modules (4) and starting up each module (4), Cutting of the elongated element (11) and / or exhaustion of the ribbons (10), and Recovery of the unconsolidated elongated textile preform (11) obtained; (ii) Consolidation of the textile preform obtained in the previous step, comprising: - a heating step in a closed mold (43) at a temperature higher than the melting temperature of the thermoplastic matrix and under pressure, the mold (43) imposing a change of shape on the preform, then - a cooling step within the mold (43) of the consolidated preform, (iii) Demolding of the composite part at a temperature lower than the crystallization temperature of the thermoplastic matrix.

[0050] Step i)

[0051] Step i) comprises the manufacture of an elongated textile and unconsolidated preform, using so-called textile ribbons, more particularly thermoplastic composite ribbons. Step i) is carried out using a specific device described in Figures 1 to 7.

[0052] For the purposes of the invention, a ribbon is said to be textile and therefore comprises fibers, for example unidirectional carbon fibers, in which case these are dry fibers. ribbon compatible with the invention is capable of being wound around the guide and comprises a structure sufficiently rigid to remain wound around the guide.

[0053] [Thermoplastic composite ribbons]

[0054] By "thermoplastic composite tape" is meant a tape comprising fibers of an inorganic or natural material and a thermoplastic polymer composition, capable of melting under the effect of temperature then solidifying, and therefore consolidating the preform.

[0055] In particular, the thermoplastic composite ribbons used in step i) may comprise: - reinforcing fibers, continuous or discontinuous, of an inorganic or natural material; and - a composition of thermoplastic polymers.

[0056] In embodiments, the thermoplastic composite ribbons comprise fibers of inorganic or natural materials: - impregnated with a composition of thermoplastic polymers (commonly called “tape”); or - or pre-impregnated with a composition of thermoplastic polymers, in particular in powder form, or - mixed with thermoplastic polymer fibers, and commonly called “combined ribbons”.

[0057] In preferred embodiments, the thermoplastic composite tape is a tape impregnated at the core with a thermoplastic polymer composition.

[0058] In embodiments, the thermoplastic composite ribbon comprises continuous fibers impregnated with a composition based on a thermoplastic polymer, having a glass transition temperature (Tg), measured according to the ISO 11357-3:2013 standard, greater than 80°C, preferably greater than or equal to 100°C, even more preferably greater than 120°C, and a melting temperature greater than 150°C when the polymer is semi-crystalline.

[0059] Preferably, the thermoplastic polymer composition of the composite tape predominantly comprises at least one thermoplastic polymer selected from: polyaryl ether ketones (PAEK), in particular poly(ether ether ketone) (PEEK); polyaryl ether ketone ketone (PAEKK), in particular poly(ether ketone ketone) (PEKK); polyaryl sulfones; polyarylsulfides, in particular polyphenylene sulfides (PPS); polyamides (PA), PEBA, polyolefins, in particular polypropylene, polylactic acid (PLA), polyvinyl alcohol (PVA), and fluoropolymers, in particular polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE) or polychlorotrifluoroethylene (PCTFE); and mixtures thereof.

[0060] Advantageously, said at least one thermoplastic polymer is selected from: polyamides, PEKK, PEI and a mixture of PEKK and PEI.

[0061] In embodiments, the thermoplastic polymer composition of the composite tape predominantly comprises a polyamide, preferably semi-crystalline.

[0062] In embodiments, the polyamide is an aliphatic, cycloaliphatic or semi-aromatic polyamide.

[0063] The aliphatic polyamide can be chosen from PA 5, PA5-10, PA6, PA66, PA6-10, PA6-12, PA6-18, PA9, PA10-10, PA 10-12, PAU, PA12, and their mixture.

[0064] The semi-aromatic polyamide can be chosen from PA MPMDT / 6T, PA 11 / 10T, PA 11 / BACT, PA 5T / 10T, PA 11 / 6T / 10T, PA MXDT / 4T, PA MXDT / 6T, PA MXDT / 10T, PA MPMDT / 4T, PA MPMDT / 6T, PA MPMDT / 10T, PA BACT / 10T, PA BACT / 6T, PA BACT / 4T, PA BACT / 10T / 6T, PA 11 / BACT / 4T, PA 11 / BACT / 6T, PA 11 / BACT / 10T, PA 11 / MXDT / 4T, PA 11 / MXDT / 6T, PA 11 / MXDT / 10T, PA 11 / MPMDT / 4T, PA 11 / MPMDT / 6T, PA 11 / MPMDT / 10T, PA 11 / MXDT / 10T, PA11 / 5T / 10T, and their mixture.

[0065] The fibers of the composite ribbons may be chosen from glass fibers, carbon fibers, basalt fibers or are basalt-based. The fibers of the composite ribbons may also be natural fibers such as flax fibers, reinforcements or bamboo fibers or hemp or cellulose fibers.

[0066] When the reinforcement is made of natural fibers or bamboo reinforcement, the thermoplastic resin will be semi-crystalline with a melting point below 250°C, preferably 220°C, even more preferably 200°C.

[0067] The fibers of the thermoplastic composite ribbons are preferably unidirectional, which means that in this case the fibers are all oriented in the same direction, i.e. along the length of the ribbon. The ribbons can also be composed of several layers of fibers superimposed on each other and having different orientations from one layer to another: however, even in this case, the fibers are non-woven and / or non-braided.

[0068] In embodiments, the composite ribbons contain a fiber content of between 40 and 70% by volume, preferably between 50 and 60% by volume of the material constituting the composite ribbons. This percentage of fibers can be determined according to well-known methods such as those described in ISO14127:2008

[0069] In embodiments, the selected ribbons (10) further comprise non-thermoplastic polymer composite ribbons (10).

[0070] In other embodiments, the non-composite thermoplastic polymer ribbons (10) represent a minority mass fraction of the preform relative to the mass fraction of the thermoplastic composite ribbons.

[0071] In still other embodiments, the polymer composition constituting the non-composite thermoplastic tapes (10) mainly comprise a polyamide, preferably semi-crystalline.

[0072] In variants of the embodiments, the ribbons (10) have a thickness of between 50 and 300 μm, in particular between 50 and 260 μm and more particularly between 60 μm and 170 μm.

[0073] In variants of the embodiments, the ribbons (10) have a width of between 5 mm and 50 mm, in particular between 10 mm and 15 mm.

[0074] The ribbons are deposited towards the guide with a winding angle strictly greater than -90° relative to the direction X of advancement of the textile element and strictly less than 90° relative to the direction X of advancement of the textile element. Each layer can have a different orientation.

[0075] In other words, the winding angle of the ribbon (10) relative to the X direction is between +90° and -90°, the limits +90° and -90° not being included.

[0076] In embodiments, the wrap angle is equal to + / -54.8° to + / -10°, preferably + / -5°, more preferably + / -1°.

[0077] According to one embodiment of the invention, the method further comprises a step of varying the diameter, or the section if it is not a tube with a circular section, of the elongated element. Means other than the implementation of the secondary guide can be implemented to enlarge or reduce the diameter, or the section if it is not a tube with a circular section, of the elongated element.

[0078] The textile preform obtained at the end of step i) generally comprises several layers, in particular as many layers as there are modules (4) used. Each layer is formed by winding a ribbon, which may be of the same or different nature, to that of the ribbon of at least one adjacent layer.

[0079] Thus, the non-composite thermoplastic ribbons can in particular be interposed between two layers of thermoplastic composite ribbon and / or constitute the internal layer of the preform and therefore of the elongated textile element after consolidation. This internal layer formed by non-composite thermoplastic ribbons can in particular play the role of a barrier layer to the fluid contained in the composite part.

[0080] In embodiments, the thermoplastic polymer composition of the thermoplastic composite ribbons (10), on the one hand, and that of the thermoplastic non-composite polymer ribbons (10) on the other hand, are compatible, in particular totally or partially miscible and are in particular identical.

[0081] When the polymer is a semi-crystalline polyamide, the total or partial compatibility of said compositions allowing their welding is defined by the ratio composed of:

[0082] - the difference in the glass transition temperatures of the two compositions present in the interfacial layer created by the weld, - related to the difference in the glass transition temperatures of the two compositions, before mixing by welding of these two compositions.

[0083] Compatibility is total when said ratio is equal to 0, and compatibility is partial when said ratio is different from 0 and less than 1, in absolute value. A total incompatibility of the polyamide included in the composition constituting the sealing layer with the polyamide included in the composition which impregnates the fibrous material of the intermediate layer is excluded. Similarly, a total incompatibility of the polyamide included in the composition which impregnates the fibrous material of the intermediate layer with the polyamide in the composition which impregnates the fibrous material of the external layer is excluded.

[0084] Advantageously, when the compatibility of said compositions is partial, said ratio is less than 30%, preferably less than 20%, in absolute value.

[0085] In embodiments, the glass transition temperature(s) of the blend, depending on whether the compatibility is total or partial, must be between the glass transition temperatures of said polyamides before blending and different from them, by at least 5°C, preferably by at least 10°C.

[0086] The expression “totally compatible” means that when, for example, two polyamides denoted PAa and PAb respectively having a Tga and a Tgb, are present respectively in two adjacent sealing layers or two reinforcement layers, and that Tga is lower than Tgb, then the mixture of the two polyamides only has a single Tgab, the value of which is between Tga and a Tgb.

[0087] Advantageously, when the compatibility of said compositions is partial, said ratio is less than 30%, preferably less than 20%, in absolute value.

[0088] In embodiments, the glass transition temperature(s) of the blend, depending on whether the compatibility is total or partial, must be between the glass transition temperatures of said polyamides before blending and different from them, by at least 5°C, preferably by at least 10°C.

[0089] The expression “totally compatible” means that when, for example, two polyamides denoted PAa and PAb having respectively a Tga and a Tgb, are present respectively in two adjacent layers, and that Tga is lower than Tgb, then the mixture of the two polyamides only has a single Tgab, the value of which is between Tga and a Tgb.

[0090] This Tgab value is then higher than Tga by at least 5°C, in particular by at least 10°C, and lower than Tgb by at least 5°C, in particular by at least 10°C.

[0091] The expression “partially compatible” means that when, for example, two polyamides PAa and PAb having a Tga and a Tgb respectively, are present respectively in two adjacent sealing layers or two reinforcing layers, then the mixture of the two polyamides has two Tg: Tg'a and Tg'b, with Tga < Tg'a < Tg'b < Tgb.

[0092] These Tg'a and Tg'b values ​​are then higher than Tga by at least 5°C, in particular by at least 10°C, and lower than Tgb by at least 5°C, in particular by at least 10°C.

[0093] An incompatibility of two polyamides results in the presence of two Tgs, Tga and Tgb, in the mixture of the two polyamides which correspond to the respective Tgs Tga and Tgb of the pure polymers taken separately.

[0094] It would not be outside the scope of the invention if the glass transition temperatures in the mixture of the two polyamides were identical or different from the temperatures before mixing, but if these two polyamides were reactive with each other.

[0095] According to other embodiments, the preform may comprise several layers of thermoplastic composite tapes, the thermoplastic polymer being able to be of the same or different nature as the thermoplastic polymer of the adjacent layer.

[0096] The preform may comprise up to 50 layers, in particular 47 layers. It may in particular comprise 10 layers of non-composite thermoplastic tapes, and 37 layers of thermoplastic composite tapes. In embodiments, the preform comprises 10 internal layers of non-composite thermoplastic tapes, forming a sealing layer after consolidation and from 10 to 50 layers of thermoplastic composite tapes, in particular 37 layers of thermoplastic composite tape, in particular impregnated at the core, forming a reinforcing layer.

[0097] In variants of the embodiments, the textile preform manufactured in step i) comprises a variation in section, in particular a narrowing of section, in particular sequential in the X direction.

[0098] In some embodiments, the cutting of the elongate element can be carried out at these sectional narrowings, and an insert can optionally be positioned there.

[0099] According to a characteristic of the invention, each module of the preform manufacturing device comprises independent supply means. Thus, each module can distribute ribbons of a different nature. The nature and dimensions of the ribbons can be different from one layer to another.

[0100] According to another characteristic of the invention, the main longitudinal guide comprises a substantially circular or polygonal section or even a free-form section. The elongated element obtained can thus have the shape of a tube or can be of a more complex shape depending on the use.

[0101] According to yet another characteristic of the invention, the supply means comprise at least one ribbon dispenser arranged around the supply ring. The implementation of the ribbon dispenser allows for easy storage and distribution of the ribbons towards the main guide, the rotating dispenser(s) around the guide according to the rotation speed of the feed crown.

[0102] According to one embodiment of the invention, the ribbon dispensers comprise pivoting means on the feed ring. The implementation of pivoting means makes it possible to orient the distribution of the ribbons towards the guide and thus to choose an angle between -90° and 90° between the ribbon and the guide. All the ribbons of the same module have substantially the same angle with the guide.

[0103] According to another embodiment of the invention, the tape dispensers comprise at least one guillotine capable of cutting at least one tape at the outlet of a dispenser and a motorized element capable of bringing the tape towards the guide.

[0104] According to another embodiment of the invention, the tape dispensers comprise welding means, for example ultrasonic welding means, capable of welding a tape to a present layer or upper layer. Other welding means compatible with the nature of the tapes used are possible within the scope of the invention. When the diameter, or the section if it is not a tube with a circular section, of the elongated element varies, it is advantageous to add or remove one or more tapes, which is possible within the scope of the invention thanks to the implementation of the guillotine and / or welding means.

[0105] According to one embodiment of the invention, the device further comprises a pulling assistance device capable of guiding the ribbons of the module(s).

[0106] The use of a pulling aid device makes it easier to slide the different layers of tape along the main guide. An example embodiment of a pulling aid device may be a system of at least one roller arranged downstream of the last module in the X direction. This or these rollers exert sufficient pressure to cause the layers of tape to slide on the main guide.

[0107] Depending on the nature of the ribbons, this assistance device can be removed during the manufacture of the textile element which, due to its rigidity, can advance alone on the guide. According to other embodiments, the nature of the ribbons does not require any pulling assistance.

[0108] According to an alternative embodiment of the invention, the device further comprises a secondary longitudinal guide of diameter or section greater than the diameter or section if it is not a tube with circular section, of the main guide and capable of translating on the main guide. When the device is in operation, the implementation of a secondary guide of greater diameter or section makes it possible to increase the diameter, or the section if it is not a tube, of the elongated element, the ribbons being deposited on the secondary guide.

[0109] The feed speed V1 corresponds to the feed speed of the textile element on the main guide. The feed speed VI is therefore substantially the same for each of the modules. The feed speed VI and the rotation speed V2 of each module are linked, on the one hand, to the angle defined between the ribbon(s) fed by each of the modules and their feed speed.

[0110] According to one embodiment of the invention, the method further comprises a step of storing the elongated element wound around a storage reel. The method according to the invention makes it possible to manufacture, until the ribbon supply means are exhausted, an elongated element of large size which can be, for example, up to a kilometer long. Storing the elongated element on a reel at the outlet of the device facilitates handling.

[0111] According to an alternative embodiment of the invention, the method further comprises the step of assisting in pulling the ribbons with the implementation of the pulling assistance device. The pulling assistance device is placed downstream of the last module delivering the last layer of the textile element. An operator can, for example, guide each of the layers of ribbon towards the pulling assistance device which will then help to slide the different layers onto the main guide.

[0112] According to one embodiment of the invention, the storage reel is a device for assisting in drawing the ribbons from the supply means of the modules of the manufacturing device.

[0113] According to one embodiment of the invention, the method further comprises the additional step of arranging a secondary longitudinal guide at the first module and translating said secondary guide along the X direction. The secondary guide makes it possible to enlarge the diameter or the section if it is not a tube, of the elongated element being manufactured or to reduce the diameter or the section of the element if a first secondary guide has already been implemented.

[0114] According to one embodiment of the invention, the method further comprises a step of bending, preferably at room temperature, the elongated element obtained at a desired angle. An advantage of the manufacturing device is the possibility of bending the elongated element at room temperature.

[0115] By “room temperature” as used in this description, we mean a temperature between 15 and 25°C.

[0116] Preferably, the absence of fogging of the thermoplastic composite ribbons making up the preform also contributes to improving the mechanical performance of the composite reinforcement. Indeed, fogging induces local over-stress at the points where the fibers cross each other and therefore constitutes a weak point from a mechanical point of view. In addition, the absence of fogging at the time of deposition results in a smaller quantity of air (and therefore defects) to be evacuated during consolidation. This reduces the cycle times and the energy consumed for consolidation, as well as the residual porosity rate.

[0117] Step ii)

[0118] The elongated textile preform obtained in step i) is then consolidated. This step consolidation comprises a heating step in a closed mold (43) at a temperature above the melting temperature of the thermoplastic matrix and under pressure, the mold imposing a change of shape on the preform, then a cooling step within the mold of the consolidated preform.

[0119] By "change of shape" within the meaning of the present invention, it is meant that the section and / or the perimeter of the preform varies. In other words, a variation is an increase or a decrease of more than 4% of the section or the perimeter measured between the preform and the final composite part, i.e. before and after steps ii) and iii). For example, if the preform is cylindrical in shape, after molding, the composite part will not be cylindrical in shape, i.e. the section will not be circular over its entire length.

[0120] The heating step is carried out at a temperature higher than the melting temperature of the thermoplastic matrix, preferably between a temperature equal to the melting temperature of the thermoplastic matrix + 5°C and the melting temperature of the thermoplastic matrix + 80°C, more particularly between a temperature equal to the melting temperature of the thermoplastic matrix + 10°C and the melting temperature of the thermoplastic matrix + 60°C.

[0121] The heating step is carried out under pressure, preferably under a pressure of between 0.5 bar and 50 bar, in particular between 0.5 bar and 10 bar, in particular between 0.5 bar and 7 bar, in particular between 1 and 7 bar.

[0122] This heating step makes it possible to weld the different layers of ribbons constituting the preform together. The heating temperature is therefore determined according to the nature of the ribbons (10) chosen.

[0123] Step ii) is carried out in a closed mold (43) external to the preform, which will deform the preform, the mold imposing a change of shape on the preform.

[0124] Preferably, the consolidation step uses a bladder placed in the preform and applying internal pressure to the preform. Thus, pressure is applied internally by means of a bladder, placed in the preform and externally by means of the walls of the mold.

[0125] Thus, during the melting of the thermoplastic matrix, the preform will take the shape of the mold. This softened preform will be sandwiched between the wall of the mold and the bladder. The application of these pressures on the softened preform makes it possible to reduce the porosity of the material. Preferably, the final composite part has a residual porosity <10%, preferably <5%, preferably <2% measured for example by image analysis or by acid digestion or carbonization according to standard ASTM D3171-15.

[0126] Then, a cooling step is carried out in the mold, still under pressure. The cooling step allows the solidification of the composite part. It is therefore It is essential that it be carried out in the closed mold so as to maintain pressure on the preform.

[0127] Preferably, consolidation step ii) is carried out under internal nitrogen pressure, which further reduces, or even completely eliminates, the risk of thermo-oxidation of the thermoplastic matrix.

[0128] Preferably, consolidation step ii) is carried out after placing the mold and the preform under vacuum, before pressurizing the bladder, which further reduces, or even completely eliminates, the risk of thermo-oxidation of the thermoplastic matrix.

[0129] Thus, step i) allows a preform to be obtained and step ii) allows the deformation of this preform. The advantage of this method is that the deformation step does not weaken the structure, but on the contrary is carried out during the consolidation of the latter.

[0130] The consolidation step comprising heating then cooling can be a few minutes, i.e. 3 minutes or on the contrary can be slow, i.e. of the order of 1 hour using low-energy cooling.

[0131] According to further embodiments of step ii), an insert may be positioned at the ends of the preform obtained in step i), preferably outside the ends of the preform. In other words, the internal surface of the insert may be in contact with the external surface of the preform.

[0132] The insert may in particular be metallic or made of a thermoplastic material, possibly composite.

[0133] Thus, in step ii), the insert can be advantageously co-consolidated with the ribbons of the preform during the consolidation step ii). When pressure is applied by means of an internal bladder to the preform, the ribbons of the preform are pressed against the internal wall of the insert, which in particular makes it possible to obtain good consolidation of the preform and also to improve the welding, and therefore the mechanical resistance, between the preform and the insert.

[0134] When the mold has low cost heating and cooling technology, the pressure applied during consolidation can be limited to less than 10 bars, preferably less than 8 bars.

[0135] According to a particular embodiment, several molds can be used in parallel, making it possible to considerably limit the manufacturing cycle time of complete parts, compared to the cycle time of conventional filament winding or thermoplastic composite ribbon winding processes.

[0136] In a preferred embodiment, and with the aim of further reducing cycle times and energy consumption, the mold used to consolidate the composite preform can be coupled to a molten polymer injection process to either finalize the part (edge ​​finishing or netshape) or to locally overmold specific features of the consolidated part (for example, reinforced plastic sleeves for subsequently assembling the tubes together or with other composite parts).

[0137] Step iii)

[0138] The method comprises a demolding step. The demolding of the composite part is carried out at a temperature lower than the crystallization temperature of the thermoplastic matrix, preferably between room temperature and the crystallization temperature, more favorably between the crystallization temperature and the glass transition temperature, more particularly still between the glass transition temperature and the glass transition temperature + 40°C.

[0139] If the demolding is carried out at a temperature above Te + 20°C, there is a risk of deformation and embrittlement of the part.

[0140] Thus, the composite part obtained has very good mechanical strength, superior to that obtained with the wet filament winding processes or the winding of conventional thermoplastic composite ribbons. Indeed, these processes do not offer the possibility of applying high pressure for a long time, and in particular when the matrix is ​​hot, that is to say during the phase of the process during which the effects of compaction are the most effective (i.e. > one minute).

[0141] Furthermore, in the case of slow cooling and the use of a semi-crystalline thermoplastic resin as the matrix of the composite, the crystallization of the resin will be optimal, which will improve the quality of mechanical and chemical resistance of the composite obtained.

[0142] When the mold has a rapid heating and cooling system, the total cycle time for manufacturing the part: cycle time for manufacturing the preform, then consolidation in a closed mold, then demolding, is much lower than the cycle time of current processes, such as wet filament winding or winding of thermoplastic composite ribbons. Preferably, the heating and cooling system increases or decreases by several tens of degrees / minute, typically greater than 10°C / min, even more favorably > 20°C / min.

[0143] In a preferred manufacturing means, several tubular preforms can be consolidated and assembled in the same mold to form composite parts with complex geometries. The parts can be assembled into each other partially or totally, or juxtaposed for local assembly, the assembly can be done by co-consolidation in the mold of the tubular preform(s) with a metal or thermoplastic part possibly loaded obtained by injection or with a textile preform of complex shape obtained by technology TFP. Composite part

[0144] According to another aspect, the invention relates to a composite part capable of being obtained according to the method as defined above.

[0145] The composite part is not tubular in shape. Its shape depends on the shape of the mold used during consolidation step ii).

[0146] The advantage of the method according to the invention is that relatively complex part shapes can be obtained.

[0147] The composite part may be provided with an insert at its ends. It may include in particular

[0148] - at least one insert provided with an orifice, and possibly

[0149] - an insert closing the elongated element and consolidated at one of its ends.

[0150] Generally speaking, the composite part can be any element of a complex structure, whatever the field of activity.

[0151] In the field of sport, the composite part can be, for example, a tennis racket, squash racket, padel racket, badminton racket, a walking stick, a ski pole, a ski lift pole, a hockey stick, a golf club, a rowing element (oar, canoe, kayak), a constituent element of a bicycle frame.

[0152] In the industrial field, the composite part can be an element of any structure, which requires a very particular design and which must present a certain mechanical resistance. Detailed description of the figures

[0153] A device according to the invention as illustrated in Figures 1 and 2 and designated as a whole by the reference 1 aims at the manufacture of a preform, that is to say an elongated textile and unconsolidated element. For these purposes, the device 1 comprises a frame 2 comprising a main longitudinal guide 3 in a direction X, and at least two modules 4 arranged in series around the guide 3 in the direction X.

[0154] The main longitudinal guide 3 is fixed on the frame 2. According to the illustrated embodiments, the main longitudinal guide 3 comprises a circular section and therefore has a tubular shape. This shape is not limiting for the invention, other shapes of guide 3 are compatible with the invention. The guide 3 is rectilinear and can comprise sections of different shapes such as square, rectangular, quadrilateral, triangular, polygonal, round, oval, or of mixed and / or free shape.

[0155] A module 4 of a device 1 according to the invention comprises, on the one hand, a feed ring 5 surrounding a section of the main longitudinal guide 3. According to the examples illustrated, the feed ring 5 has substantially the shape of a disc comprising a central hole in which the guide 3 is located.

[0156] A module 4 further comprises feed means 6 arranged on the crown 5. According to the illustrated embodiment, the feed means 6 are located on one face of the disc and feed at least one ribbon 10 towards the guide 3 with an angle relative to the direction X of between - 90° and + 90°.

[0157] A ribbon 10 compatible with the invention is, on the one hand, sufficiently flexible to be wound around the guide 3.

[0158] The feed means 6 arranged on the crown 5 feed at least one ribbon 10 towards the guide 3 with a chosen angle of between -90° and 90° relative to the direction X. Each ribbon 10 is wound at least around the guide 3 or on the layer of ribbon 10 already present, i.e. the upper layer with a chosen overall feed speed VI.

[0159] Each module 4 also comprises drive means 15 for the crown 5. According to [Fig.2] and also visible in [Fig.3], the drive means 15 are located on the face of the crown 5 opposite the feed means 6. The drive means 15 for the crown 5 make it possible to rotate the crown 5 around the guide 3 at a rotation speed V2. According to the illustrated embodiment, the drive means 15 comprise a motor comprising in particular a belt capable of rotating the crown 5 and a motor control unit in order to implement a rotation speed V2 of the crown 5. This configuration is not limiting for the invention.

[0160] The device illustrated in Figures 1 and 2 comprises two modules 4. The supply means 6 of the first module 4 comprise two dispensers 20 of ribbon 10 and the supply means 6 of the second module 4 comprise a single dispenser 20 of ribbon 10. The supply means 6 of the different modules 4 are in fact independent of each other. Thus each module 4 can deliver ribbons 10 of different nature and a chosen number of ribbons 10 per layer.

[0161] [Fig.4] illustrates a module 4 comprising six dispensers 20 of ribbon 10. The dispensers 20 of ribbon 10 are arranged around the supply ring 5. According to the illustrated embodiments, a dispenser 20 of ribbon 10 comprises a reel 21 fixed on one face of the ring 5 with pivoting means 22.

[0162] According to this illustrated but non-limiting embodiment, the pivoting means 22 comprise a fixed part 23 and a pivoting part 24 directed towards the coil 21. The coil 21 is free to pivot in the pivoting part 24 and the pivoting part is free to pivot relative to the fixed part 23. Thus, the coil 21 can be arranged according to a desired configuration and the pivoting means 22 can be locked according to the desired arrangement of the distributor 20.

[0163] [Fig.5] illustrates a particular embodiment of the invention in which a dispenser 20 of ribbon 10 also comprises a guillotine 25 capable of cutting the ribbon 10 at the outlet of the dispenser 20, a motor M capable of feeding the ribbon after cutting and ultrasonic welding means 26 capable of welding a ribbon 10 at the level of a layer of ribbons 10 present or upper layer. The illustration of the motor M, the guillotine 25 and the welding means 26 is schematic in [Fig.5] and other embodiments are possible and in particular with means of acting on a ribbon 10 outside the dispenser 20.

[0164] Figures 6 and 7 illustrate a particular embodiment of the invention. The device 1 comprises three modules 4. The first module 4 comprises four dispensers 20 of ribbon 10 which each deposit a ribbon 10 in the direction of advancement X, that is to say that the angle between the ribbon 10 and the guide 3 has a value of 0 degrees. The second module 4 comprises two dispensers 20 of ribbon 10 and finally the third module 4 comprises a single dispenser 20 of ribbon 10. This embodiment is not limiting for the invention.

[0165] In order to manufacture an elongated element 11 according to the invention, a first step consists of implementing supply means 6 on each of the modules 4 of the device 1. For this purpose, according to the examples illustrated, reels 21 each comprising a chosen ribbon 10 are arranged on each supply ring 5 of the device 1.

[0166] Preferably, the reels deliver the same ribbon 10 per module and each module 4 may comprise reels of ribbon 10 of different type.

[0167] According to the example illustrated in Figures 8 and 9, the ribbons 10 used have a width of between 20 and 10 mm and a thickness of approximately 150 microns.

[0168] A second step of the method consists in setting, on the one hand, the feed speed VI and, on the other hand, the rotation speed V2 of each of the modules 4. The precise and coordinated setting of these two values ​​makes it possible to define for each feed means 6 a desired angle between the ribbon 10 and the guide, this angle varies between -90 and +90° excluding these two interval limits. For example, and according to the example of the device illustrated in Figures 8 and 9, a first layer of ribbon 10 is deposited with an angle close to 0° relative to the X direction, a second layer of ribbon 10 is deposited with an angle of approximately 80° relative to the X direction and a third layer is deposited with an angle close to -80° relative to the X direction.

[0169] An example of parameterization consists of defining a feed speed VI substantially equal to one meter per minute and a rotation speed V2 of two modules 4 each distributing a ribbon 10 substantially equal to 360 revolutions per minute. This example is not limiting for the invention.

[0170] Modules 4 are then started.

[0171] Depending on the nature of the ribbons 10, a pulling assistance device 30 is implemented in order to to assist in pulling the ribbons 10 from the different layers of the element 11. According to the embodiment illustrated in Figures 8 and 9, the first layer of ribbon 10 from the first module 4 slides on the main guide 3 through the two other modules 4 implemented. The ribbons 10 of the first layer can slide alone if their nature allows it or with manual assistance. The ribbons 10 of the other layers are deposited on the previous layer and then pass through the pulling assistance device 30. This assistance device 30 is not always necessary for implementing the method but it can assist in sliding the different layers towards the X direction depending on the nature of the ribbons 10 used.

[0172] According to a particular embodiment with in particular ribbons of the first layer arranged at an angle close to 0° with the direction X, there is not necessarily a need for manual assistance to advance said ribbons 10.

[0173] According to another embodiment, once other layers of ribbons 10 are superimposed on the first layer, the elongated element 11 is manufactured without assistance and the pulling aid device 30 is no longer useful and can be removed. This may be a transitional period of start-up assistance which is necessary if the nature of the ribbon 10 used does not allow the ribbon to deploy efficiently from its reel 21.

[0174] The elongated element 11 which is manufactured can be stored wound around a storage reel, thus facilitating its subsequent handling. The elongated element 11 can also be cut as it is manufactured according to the desired size and according to the additional steps described below, for example increasing or reducing the dimensions.

[0175] According to one embodiment (not illustrated) the storage reel is a device for assisting in pulling the ribbons 10. In fact, when it is wound, the textile element 11 causes the ribbons 10 which form it to be pulled.

[0176] When the elongated element 11 is of the desired size, it can then be cut. Another way of completing the process is to wait until the ribbons 10 are used up.

[0177] The obtained unconsolidated textile elongated element 11 can finally be recovered. Consolidation steps can then be applied to it, for example a thermoforming step when the dimensions allow it. When consolidating the elongated element 11, it is also possible to slightly vary the dimensions of the elongated element 11, in particular its perimeter, of the order of 10-20%.

[0178] According to a particular embodiment, a secondary longitudinal guide (not shown) is arranged at the level of the first module 4 during manufacturing. This secondary guide of diameter or section greater than the diameter or section of the main guide 3 is placed upstream of the first module 4 and translates towards the manufacturing direction of the elongated element 11. The ribbons 10 of the different modules 4 are then deposited on the secondary guide, and again on the main guide 3 after the passage of the secondary guide. It is thus also possible to significantly increase the diameter or the section or even the overall shape of the elongated element 11 during its manufacture.

[0179] [Fig.8] is a diagram showing the implementation of the method according to the invention. Step A represents the mold 43, consisting of an upper part 41 and a lower part 42 and the elongated textile and unconsolidated element, i.e. the preform 40. Step B represents the preform 40 positioned in the lower part 42 of the mold 43. Step C represents the mold 43 in the closed position. Step D represents the mold D in the open position after the consolidation step ii).

[0180] [Fig.9] is a perspective view of the final composite part 44, which has undergone the process according to the invention. This figure shows the complex shape obtained, and imposed by the mold.

[0181] Of course, various other modifications may be made to the invention within the scope of the appended claims.

Claims

Claims

1. Method of manufacturing a composite part, said method comprising the following successive steps: (i) Manufacture of an elongated, unconsolidated textile preform using a device (1) comprising: - a frame (2) comprising a main longitudinal guide (3) in a direction X, said guide (3) being fixed on the frame (2) and - at least two modules (4) arranged in series around the guide (3) in the X direction, each module (4) comprising: - a feed ring (5) surrounding a section of the guide (3), - feed means (6) arranged on the ring (5) capable of feeding at least one ribbon (10) towards the guide (3) at a winding angle of between -90° and 90° with the direction X and at a feed speed VI, each ribbon (10) being capable of winding at least around the guide (3) or on the upper layer of ribbon (10), and - drive means (15) of the ring (5) capable of rotating the ring (5) around the guide (3) at a rotation speed V2, Said preform being manufactured according to a process comprising the steps of: Implementation of the supply means (6) on each of the modules (4), said supply means (6) comprising selected ribbons (10), said selected ribbons (10) comprising at least thermoplastic composite ribbons Setting the feed speed VI and the rotation speed V2 of each of the modules (4) and starting up each module (4), Cutting the elongated element (11) and / or exhausting the ribbons (10), and Recovery of the unconsolidated elongated textile preform (11) obtained; (ii) Consolidation of the textile preform obtained in the previous step, comprising: - a heating step in a closed mold (43) at a temperature higher than the melting temperature of the thermoplastic matrix and under pressure, the mold (43) imposing a change of shape on the preform, then - a cooling step within the mold (43) of the consolidated preform (iii) Demolding of the composite part at a temperature lower than the crystallization temperature of the thermoplastic matrix.

2. A method according to claim 1, wherein the heating step of step ii) is carried out at a temperature between a temperature equal to the melting temperature of the thermoplastic matrix + 5°C and the melting temperature of the thermoplastic matrix + 80°C, more particularly between a temperature equal to the melting temperature of the thermoplastic matrix + 10°C and the melting temperature of the thermoplastic matrix + 60°C.

3. Method according to claim 1 or 2, wherein the heating step of step ii) is carried out at a pressure of between 0.5 bar and 50 bar, in particular between 0.5 bar and 10 bar, in particular between 0.5 bar and 7 bar, in particular between 1 and 7 bar.

4. A method according to any preceding claim, wherein consolidation step ii) uses a bladder placed in the preform and applying internal pressure.

5. A method according to any preceding claim, wherein a bending step is performed before the consolidation step ii'»

6. n j. A method according to any preceding claim, wherein the thermoplastic composite tapes comprise: - Continuous or discontinuous reinforcing fibers of an inorganic or natural material; and - A thermoplastic polymer composition.

7. A method according to any one of the preceding claims, wherein the reinforcing fibers of an inorganic or natural material are: - impregnated or pre-impregnated with a composition of thermoplastic polymers, or - mixed with fibers of thermoplastic polymer(s).

8. A method according to any one of the preceding claims, wherein the thermoplastic polymer composition of the composite tape predominantly comprises at least one thermoplastic polymer selected from: polyaryl ether ketones (PAEK), in particular poly(ether ether ketone) (PEEK); polyaryl ether ketone ketone (PAEKK), in particular poly(ether ketone ketone) (PEKK); polyaryl sulfones; polyarylsulfides, in particular polyphenylene sulfides (PPS); polyamides (PA), in particular semi-aromatic polyamides (polyphthalamides) optionally modified with urea units; PEBA, polyolefins, in particular polypropylene, polylactic acid (PLA), polyvinyl alcohol (PVA), and fluoropolymers, in particular polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE) or polychlorotrifluoroethylene (PCTFE); and mixtures thereof, preferably, the thermoplastic polymer composition of the composite tape comprises predominantly a polyamide, preferably semi-crystalline.

9. A method according to claim 8, wherein the thermoplastic polymer is an aliphatic, cycloaliphatic or semi-aromatic polyamide.

10. A method according to any preceding claim, wherein the fibers of the thermoplastic composite tapes are selected from glass fibers, carbon fibers, basalt or basalt-based fibers, or are natural fibers such as flax fibers, reinforcements or bamboo fibers or hemp or cellulose fibers.

11. A method according to any preceding claim, wherein the fibers of the thermoplastic composite ribbons are unidirectional, i.e. all oriented along the length of the ribbon.

12. A method according to any one of the preceding claims, wherein the composite ribbons contain a fiber content of between 40 and 70% by volume, preferably between 50 and 60% by volume of the thermoplastic composite ribbons.

13. A method according to any preceding claim, wherein the selected ribbons (10) comprise non-composite ribbons (10) of thermoplastic polymer.

14. Method according to any one of the preceding claims, in which the ribbons (10) have a thickness of between 50 and 300 pm, in particular between 50 and 260 pm and more particularly between 60 pm and 170 pm.

15. Method according to any one of the preceding claims, in which the ribbons (10) have a width of between 5 mm and 50 mm, in particular between 10 mm and 15 mm.

16. A method according to any preceding claim, in in which the winding angle of the ribbon (10) relative to the X direction is between +90° and -90°.

17. Composite part of non-cylindrical shape capable of being obtained according to the method as defined in claims 1 to 16.

18. Use of the composite part as defined in claim 17 as an element of a sporting article, preferably a bicycle frame, a snowshoe frame, a ski pole, a hiking pole, a hockey stick, a golf club, a rowing element (oar, canoe, kayak).

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