Sound absorbing laminated composite structures for aircraft structures

Abstract

The present invention relates to the field of aircraft structures and structural materials for such aircraft, and in particular to the field of noise-absorbing materials for aircraft structures. The present invention provides a sound-absorbing laminated composite material structure for aircraft structures, a method for manufacturing the sound-absorbing laminated composite material structure, and an aircraft.

Description

Technical Field

[0001] The present invention belongs to the field of aircraft structures and structural materials for these aircraft, in particular to the field of noise-absorbing materials for aircraft structures. Background Art

[0002] In common aircraft structures, existing carbon fiber reinforced polymer (CFRP) structures lack the ability to absorb noise, such as that from aircraft engines. In most cases, the noise impact of these structures needs to be reduced, and additional layers of absorbing material are positioned at strategic points in such CFRP structures to achieve this.

[0003] Existing solutions for integrating absorbent materials into CFRP structures are based on bonding continuous plies of elastomeric material to carbon plies by adhesive connections. This solution reduces the structural strength of such structures due to the lack of shear load transfer and also due to the strain incompatibility of the materials.

[0004] In order to reduce the noise impact on a specific aircraft structure (ie, the passenger cabin) without compromising the structural efficiency (weight / strength), it is necessary to easily integrate the material into the specific aircraft structure.

[0005] The present invention therefore provides a laminate composite structure for aircraft structures that absorbs sound waves and addresses the above-mentioned disadvantages. Summary of the Invention

[0006] The present invention aims at the above problems and provides an alternative solution through a sound wave absorbing laminated composite material structure, a method for manufacturing a sound wave absorbing laminated composite material structure, and an aircraft. Preferred embodiments of the present invention are also defined herein.

[0007] In a first inventive aspect, the present invention provides a sound wave absorbing laminate composite structure for an aircraft structure, the laminate composite structure comprising at least three stacked plies of a hybrid composite material, each hybrid composite ply comprising a combination of:

[0008] a plurality of first polymer material tows arranged parallel to the warp direction, wherein each first polymer material tow has a first width W1,

[0009] a plurality of second polymeric material tows arranged parallel to the weft direction, wherein each second polymeric material tow has a third width W3, and

[0010] a plurality of absorbent material tows arranged parallel to said warp direction, wherein each absorbent material tow has a second width W2,

[0011] in,

[0012] The polymer material tow is a carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP) tow; and

[0013] The plurality of first polymeric material tows and the plurality of second polymeric material tows and the plurality of absorbent material tows are arranged to interweave therebetween to form a pattern for each hybrid material ply such that the acoustic wave absorbing laminate composite structure achieves an improved level of absorption for acoustic waves having a wavelength λ that conforms to the following formula:

[0014] λ<(2×W2+W1).

[0015] A hybrid composite material is understood to be a combination of materials of different nature, in particular a combination of a plastic material and an absorbent material. This interweaving of polymer material tows and absorbent tows provides a hybrid composite ply that advantageously increases sound absorption efficiency while having a low impact on shear load transfer.

[0016] The sound absorbing laminate composite structure advantageously transfers forces to adjacent hybrid composite plies and can reduce noise introduced into the aircraft structure (ie, motor noise and turbulence noise introduced into the aircraft cabin).

[0017] The present laminated composite structure includes at least three stacked hybrid composite plies, which is the minimum number of plies required for the laminated composite structure to absorb nearly the entire wavelength without degrading the mechanical properties of the structure.

[0018] The first polymer material tow and the second polymer material tow are plastic materials reinforced by carbon fiber (CF) or glass fiber (GF).These polymer material tows provide mechanical properties to the hybrid composite material and serve as the main matrix of the hybrid material.

[0019] The laminated composite structure of the present invention absorbs noise and transmits shear forces in a single structural performance thanks to the combination of at least three hybrid composite plies.

[0020] The specific distribution of the polymer material tows in both the warp and weft directions and the interweaving of the absorbent material tows with the polymer material tows in the warp direction provide a hybrid composite ply pattern with high sound absorption efficiency. The warp direction is perpendicular to the weft direction.

[0021] Thus, the present laminated composite structure advantageously reduces the noise impact within an aircraft interior without compromising structural efficiency (weight / strength), and is an integral material for manufacturing aircraft structures. Furthermore, currently used manufacturing techniques are maintained, and therefore the impact on production rates and production procedures is minimal.

[0022] In certain embodiments, the laminated composite structure includes a plurality of carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP) composite plies, with one composite ply interposed between every two consecutive hybrid composite plies.

[0023] Such a combination of CFRP or GFRP layups and hybrid composite layups advantageously provides a laminate composite structure that meets high structural requirements with regard to stiffness.

[0024] In a particular embodiment, the first width W1 is equal to the third width W3. Advantageously, such equal widths of the polymer material tows in the warp direction and the polymer material tows in the weft direction maintain balance and equilibrium between the two fabric axes and simplify the raw material supply of the fabric compound.

[0025] In a particular embodiment, the pattern is a 2 x 2 twill weave carbon fiber pattern.

[0026] In another particular embodiment, the pattern is a 5-strand carbon fiber pattern.

[0027] In a specific embodiment, the at least three stacked plies of hybrid material are stacked with parallel stacking planes therebetween in such a manner that:

[0028] The first hybrid composite material ply is arranged in a first direction,

[0029] The second hybrid composite ply is arranged in a second direction, and

[0030] The third hybrid composite material layer is arranged in the third direction accordingly.

[0031] The second direction forms an angle of +45° with respect to the first direction, and the third direction forms an angle of -45° with respect to the first direction.

[0032] This stacking of hybrid composite plies with different arrangements of each ply provides an acoustic network for increasing the specific surface area of ​​the acoustic material, which advantageously reduces the wavelength of the transmitted sound waves.

[0033] According to the laminated composite structure, each hybrid composite ply is included in a stacking plane such that the stacking planes of all hybrid composite plies are parallel between them. It should be understood in this document that for the first hybrid material ply, the warp direction of the first polymer material tows and the absorbent material tows is a first direction; for the second hybrid composite ply, the direction of the first polymer material tows and the absorbent material tows is a second direction; and for the third hybrid composite ply, the direction of the first polymer material tows and the absorbent material tows is a third direction; such that in a specific example, the second direction forms +45° relative to the first direction, and the third direction forms -45° relative to the first direction. That is, if all three hybrid composite plies are laminated with the same lamination direction, each hybrid composite ply is rotated relative to the remaining hybrid composite plies when stacking the hybrid composite plies.

[0034] In another specific embodiment, the sound-absorbing laminate composite structure includes, in stacking order: thirty composite plies, a first hybrid composite ply, one composite ply, a second hybrid composite ply, one composite ply, a third hybrid composite ply, and three composite plies, wherein

[0035] The first hybrid composite material plies are arranged in a first direction,

[0036] The second hybrid composite material plies are arranged in a second direction, and

[0037] The third hybrid composite material ply is correspondingly arranged in the third direction,

[0038] wherein the first direction forms an angle of +45° relative to the second direction, and the third direction forms an angle of +135° relative to the second direction; and

[0039] Wherein, the composite material ply is preferably carbon fiber reinforced polymer.

[0040] The laminated composite structure is configured to protect an auxiliary power unit (APU) and provide an aerodynamic enclosure for the entire fuselage of an aircraft. For structural requirements (i.e., fire protection requirements), the hybrid composite layup is positioned as far away from the APU as possible, with the thirty composite layups being located closer to the APU. Furthermore, the three composite layups improve the manufacturing and assembly tasks for this particular laminate. Advantageously, this configuration of the laminated composite structure provides an acoustic network for increasing the specific surface area of ​​the acoustic material, which serves to reduce the wavelength of the transmitted sound waves.

[0041] In certain embodiments, the absorbent material is a pure insulating material comprising tows of elastomeric material.

[0042] The use of an elastomeric material as an absorbing material advantageously provides a high degree of absorption of noise in the laminate composite structure. That is, due to the inherent properties (elasticity) of the elastomeric material, it is able to absorb sound waves.

[0043] In a particular embodiment, the absorbent material is a reinforced insulating material comprising tows of an elastomeric material and a reinforcing carrier embedded in the elastomeric material. More particularly, the carrier is a carbon fiber (CF) or glass fiber (GF) mesh.

[0044] These reinforcement carriers are carbon or glass fiber grids embedded in the elastomeric material during the polymerization process, with the aim of increasing the overall stiffness of the material in its two main directions (longitudinal and transverse) to improve the production process and the forming compatibility between the polymer material tows.

[0045] Carbon fiber reinforced elastomeric materials are provided for combination with carbon fiber materials, and glass fiber reinforced elastomeric materials are provided for combination with glass fiber materials.

[0046] Furthermore, the reinforcing carrier embedded in the elastomeric material advantageously improves deformation compatibility within the absorbent material due to the similar stiffness of the different materials. That is, the stiffness of the reinforced elastomeric material approximates that of the polymer tow, which improves the overall elastic properties of the hybrid material. Furthermore, increasing the elastic limit of the absorbent material (provided the reinforced elastomeric material) allows for higher load levels required to enter a plastic deformation state, thereby allowing for higher overall force levels within the hybrid material.

[0047] In a second aspect of the invention, the present invention provides a method for manufacturing the sound wave absorbing laminate composite structure of the present invention, the method comprising the following steps:

[0048] a) providing at least three hybrid composite layups,

[0049] b) laminating / stacking at least three hybrid composite plies,

[0050] c) bonding at least three hybrid composite plies, and

[0051] d) obtaining a laminated composite material;

[0052] Each hybrid composite layup is manufactured through the following steps:

[0053] i) providing a plurality of tows of a first polymeric material in a warp direction,

[0054] ii) providing a plurality of second polymeric material tows in a weft direction, each second polymeric material tow being interwoven with a plurality of first polymeric material tows,

[0055] iii) providing a plurality of absorbent material strands in the warp direction, each absorbent material strand being interwoven with a first polymeric material strand and a second polymeric material strand,

[0056] In the manufacture of the hybrid composite material ply, the first polymer material tows and the absorbent material tows are prestressed with a first stress and a second stress, respectively, and the second polymer material tows are responsible for interweaving with the first polymer material tows and the absorbent material tows.

[0057] In certain cases, where the absorbent material is an elastomeric material, the elastomeric material is carbon fiber or glass fiber reinforced and embedded in the carrier together with the elastomeric material to allow for a higher pre-tensioning force to be provided to the absorbent material and to facilitate the organization process of the hybrid material.

[0058] In a particular embodiment, for prepreg materials, step c) of bonding comprises compacting and curing (preferably by autoclave) the stack. In another particular embodiment, for dry fiber materials, step c) of bonding comprises consolidating the stack by resin transfer molding (RTM).

[0059] In a specific embodiment, step b) comprises the following steps:

[0060] - stacking a first ply of hybrid material in a first direction,

[0061] - stacking a second hybrid material ply in a second direction forming +45° with respect to the first direction,

[0062] - stacking a second hybrid material ply in a third direction forming -45° with respect to the first direction.

[0063] This stacking of hybrid composite plies with different arrangements of each ply provides an acoustic network for increasing the specific surface area of ​​the acoustic material, which advantageously reduces the wavelength of the transmitted sound waves.

[0064] In another specific embodiment, step b) comprises the following steps:

[0065] - stacking a first ply of hybrid material in a first direction,

[0066] - stacking a second hybrid material ply in a second direction forming +45° with respect to the first direction,

[0067] - stacking a second ply of mixed material in a third direction,

[0068] The first direction forms an angle of +45° relative to the second direction, and the third direction forms an angle of +135° relative to the second direction.

[0069] In certain embodiments, the method further includes providing a plurality of composite plies of CFRP or GFRP, and laminating such CFRP or GFRP plies in a manner such that the CFRP and GFRP plies are interposed between the hybrid composite plies.

[0070] In a specific embodiment, according to an embodiment of the sound wave absorbing laminated composite structure of the first inventive aspect, the method further comprises stacking thirty composite plies and three composite plies.

[0071] In a third inventive aspect, the present invention provides an aircraft comprising an aircraft structure made from the sound-absorbing laminate composite material structure according to any one of the first inventive aspects.

[0072] All features described in this specification (including claims, description and drawings) and / or all steps of the methods described may be combined in any combination, except combinations of those mutually exclusive features and / or steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] These and other characteristics and advantages of the present invention will be clearly understood in light of the detailed description of the invention with reference to the accompanying drawings, which will become apparent from the preferred embodiments of the present invention which are given by way of example only and are not intended to be limiting thereof.

[0074] Figure 1 This figure shows a schematic cross-sectional view of a sound wave absorbing laminate composite material structure according to a first embodiment of the present invention.

[0075] Figure 2 This figure shows a schematic cross-sectional view of a sound wave absorbing laminate composite material structure according to a second embodiment of the present invention.

[0076] Figure 3 This figure shows a schematic cross-sectional view of a sound wave absorbing laminate composite material structure according to a third embodiment of the present invention.

[0077] Figure 4 This figure shows a top view of a hybrid composite layup of a sound-absorbing laminate composite structure according to an embodiment of the present invention.

[0078] Figure 5 This figure shows a top view of a hybrid composite layup of a sound wave absorbing laminate composite material according to an embodiment of the present invention.

[0079] Figure 6 This figure shows an exploded view of a hybrid composite layup of a sound wave absorbing laminate composite material according to an embodiment of the present invention.

[0080] Figure 7This figure shows an aircraft according to an embodiment of the invention. DETAILED DESCRIPTION

[0081] Figure 1 A cross-sectional view of a sound wave absorbing laminate composite structure (1) for aircraft structures is shown. According to a first embodiment of the present invention, the laminate composite structure (1) comprises three hybrid composite layups (2).

[0082] Figure 2 A cross-sectional view of a second embodiment of a sound wave absorbing laminated composite structure (1) for aircraft structures is shown. The laminated composite structure (1) comprises three hybrid composite plies (2: 2.1, 2.2, 2.3) and four carbon fiber reinforced polymer (CFRP) composite plies (6). The hybrid composite plies (2) are interposed between the CFRP plies (6).

[0083] In a specific example, the first hybrid composite layup (2.1) is arranged in a first direction (d1), the second hybrid composite layup (2.2) is arranged in a second direction (d2), and the third hybrid composite layup (2.3) is correspondingly arranged in a third direction (d3). The second direction (d2) forms a +45° angle relative to the first direction (d1), and the third direction (d3) forms a -45° angle relative to the first direction (d1).

[0084] Figure 3 A cross-sectional view of a third embodiment of a sound wave absorbing laminated composite structure (1) for a rear structure of an aircraft for protecting an auxiliary power unit (APU) is shown. The laminated composite structure (1) comprises, from the outside to the inside of the aircraft: thirty composite layups (6), a first hybrid composite layup (2.1), one composite layup (6), a second hybrid composite layup (2.2), one composite layup (6), a third hybrid composite layup (2.3), and three composite layups (6). In a specific example, the first hybrid composite layup (2.1) is arranged in a first direction (d1), the second hybrid composite layup (2.2) is arranged in a second direction (d2), and the third hybrid composite layup (2.3) is arranged in a third direction (d3) accordingly. The first direction (d1) forms +45° with respect to the second direction (d2), and the third direction (d3) forms +135° with respect to the second direction (d2). The composite layups (6) are preferably carbon fiber reinforced polymer (CFRP).

[0085] Figure 4 and Figure 5A hybrid composite material ply (2) is shown, comprising a plurality of first polymer material tows (3) (indicated by dots), a plurality of second polymer material tows (4) (indicated by dashed lines), and a plurality of absorbent materials (5). The polymer material tows (3, 4) are plastic materials reinforced with carbon fibers or glass fibers. Figure 4 and Figure 5 wherein the absorbent material (5) is an elastomeric material. The first polymer material strands (3) are arranged in the warp direction (d 经线 ), and each first polymer material tow (3) comprises a first width W1. The second polymer material tow (4) is arranged in the weft direction (d 纬线 ), and each second polymer material tow (4) comprises a third width W3. The elastomeric material tows (5) are arranged in the warp direction (d 经线 ) are parallel to the first polymer material tows, and each elastomeric material tow (5) comprises a second width W2. In a particular embodiment, the first width W1 is equal to the third width W3.

[0086] exist Figure 4 As can be observed, the first polymer material tows (3) and the second polymer material tows (4) and the elastomeric material tows (5) are interwoven therebetween to form a 2 x 2 twill weave carbon fiber pattern (8).

[0087] exist Figure 5 In the embodiment, the first polymer material tow (3), the second polymer material tow (4) and the elastomeric material tow (5) are interwoven to form a 5-bundle carbon fiber pattern (8).

[0088] The acoustic properties of the present laminated composite structure (1) depend on the width of the filament bundles forming each hybrid composite layer (2), because the wavelength attenuation depends on the width. Therefore, the present laminated composite structure (1) is suitable for absorbing wavelengths (λ) at different absorption levels. For small wavelength absorption, the expression (2×W2+W1) must be greater than the wavelength (λ). For general wavelength absorption, the first width W1 must be less than the wavelength (λ). For large wavelength absorption, the expression (2×W2+W1) must be greater than the wavelength (λ), and the wavelength must also be greater than the first width W1.

[0089] Furthermore, the present sound wave absorbing laminated composite structure (1) is capable of transferring shear forces of the aircraft structure through the tows contained in each hybrid composite ply (2).

[0090] The present invention further provides a method of making a sound-absorbing laminate composite structure (1), the method comprising the steps of:

[0091] a) providing at least three hybrid composite material layups (2),

[0092] b) stacking at least three hybrid composite material plies (2),

[0093] c) bonding at least three hybrid composite plies (2), and

[0094] d) obtaining a laminated composite material (1);

[0095] Each hybrid composite material layer (2) is manufactured by the following steps:

[0096] i) In the direction of longitude (d 经线 ) providing a plurality of first polymer material tows (3),

[0097] ii) In the latitude direction (d 纬线 ) providing a plurality of second polymer material tows (4), each second polymer material tow (4) being interwoven with the plurality of first polymer material tows (3),

[0098] iii) in the direction of the meridian (d 经线 ) providing a plurality of absorbent material tows (5), each absorbent material tow (5) being interwoven with a first polymer material tow (3) and a second polymer material tow (4),

[0099] In the manufacture of the hybrid composite material ply, the first polymer material tow (3) and the absorbent material tow (5) are prestressed with a first stress and a second stress respectively, and the second polymer material tow (4) is responsible for being interwoven with the first polymer material tow (3) and the absorbent material tow (5).

[0100] In the manufacturing step of the hybrid composite material layup (2), first, the first polymer material tows (3) and the absorbent material tows (5) are arranged in the warp direction (d 经线 ) are prestressed with a first stress and a second stress respectively; secondly, the second polymer material tow (4) is prestressed with the first polymer material tow (4) and the absorbent material tow (5) in the weft direction (d 纬线 ) are interwoven with each other. In this way, all the tows (3, 4, 5) are interwoven with each other between them.

[0101] In a particular embodiment, wherein the laminated composite structure (1) comprises three hybrid composite plies (2) (e.g. Figure 1 or and Figure 2 As shown), the stacking of the hybrid composite material plies (2) is performed by the following steps:

[0102] - stacking a first hybrid material ply (2.1) in a first direction (d1),

[0103] - stacking a second hybrid material ply (2.2) in a second direction (d2) forming +45° with respect to said first direction (d1),

[0104] - stacking a second hybrid material ply (2.3) in a third direction (d3) forming -45° with respect to said first direction (d1).

[0105] Figure 6 An exploded view of an embodiment of three hybrid composite plies (2: 2.1, 2.2, 2.3) of a laminated composite structure (1) is shown. In this figure, the orientation of each ply (2.1, 2.2, 2.3) according to this particular embodiment can be identified. The first hybrid composite ply (2.1) is oriented in a first direction (d1) in the laminated composite material. The second hybrid composite ply (2.2) is oriented in a second direction (d2) in the laminated composite material that forms a +45° angle relative to the first direction (d1). The third hybrid composite ply (2.3) is oriented in a third direction (d3) in the laminated composite material that forms a -45° angle relative to the first direction (d1).

[0106] exist Figure 6 The three hybrid composite layups (2.1, 2.2, 2.3) shown in FIG. 1 include Figure 4 Example patterns shown.

[0107] Figure 7 An aircraft (7) is shown that includes an aircraft structure (not shown) made from the acoustically absorbing laminate composite structure (1). In a specific embodiment, the aircraft structure is a fan fairing. In another specific embodiment, the aircraft structure is a passenger cabin. In another specific embodiment, the aircraft structure is a tail cone or rear section of the aircraft.

Claims

1. A sound wave absorbing laminate composite structure for an aircraft structure, the laminate composite structure comprising at least three stacked plies of a hybrid composite material, each hybrid composite ply comprising a combination of: - a plurality of first polymer material tows arranged parallel to the warp direction (d 经线 ),in, Each tow of the first polymeric material has a first width W1, - a plurality of second polymer material tows arranged parallel to the weft direction (d 纬线 ),in, Each tow of the second polymeric material has a third width W3, and - a plurality of absorbent material strands arranged parallel to said warp direction (d 经线 ), wherein each absorbent material tow has a second width W2, in, The polymer material tow is a carbon fiber reinforced polymer (CFRP) tow or a glass fiber reinforced polymer (GFRP) tow; and The plurality of first polymeric material tows and the plurality of second polymeric material tows and the plurality of absorbent material tows are arranged to interweave therebetween to form a pattern for each hybrid material ply such that the acoustic wave absorbing laminate composite structure achieves an improved level of absorption for acoustic waves having a wavelength λ that conforms to the following formula: λ<(2×W2+W1).

2. The sound wave absorbing laminate composite structure according to claim 1, further comprising a plurality of composite plies of carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP), with one composite ply being interposed between every two consecutive hybrid composite plies.

3. A sound absorbing laminate composite structure according to any one of the preceding claims, wherein: The first width W1 is equal to the third width W3.

4. The sound wave absorbing laminated composite material structure according to any one of claims 1 to 2, wherein: The pattern is a 2 x 2 twill weave carbon fiber pattern.

5. The sound wave absorbing laminated composite material structure according to any one of claims 1 to 2, wherein: The pattern is a 5 strand carbon fiber pattern.

6. The sound wave absorbing laminated composite material structure according to any one of claims 1 to 2, wherein: The at least three stacked plies of hybrid material are stacked with parallel stacking planes therebetween in such a manner that: The first hybrid composite material ply is arranged in a first direction (d1), The second hybrid composite ply is arranged in a second direction (d2), and The third hybrid composite layer is arranged in the third direction (d3) accordingly. The second direction (d2) forms +45° with respect to the first direction (d1), and the third direction (d3) forms -45° with respect to the first direction (d1).

7. The sound wave absorbing laminated composite material structure according to any one of claims 1 to 2, comprising, in stacking order: Thirty composite layups, a first hybrid composite layup, a composite layup, a second hybrid composite layup, a composite layup, a third hybrid composite layup, and three composite layups, wherein The first hybrid composite material ply is arranged in a first direction (d1), The second hybrid composite ply is arranged in a second direction (d2), and The third hybrid composite material ply is correspondingly arranged in a third direction (d3), wherein the first direction (d1) forms +45° with respect to the second direction (d2), and The third direction (d3) forms +135° with respect to the second direction (d2); and Wherein, the composite material ply is carbon fiber reinforced polymer (CFRP).

8. The sound wave absorbing laminated composite material structure according to any one of claims 1 to 2, wherein: The absorbent material is a pure insulating material comprising tows of elastomeric material.

9. The sound wave absorbing laminated composite material structure according to any one of claims 1 to 2, wherein: The absorbent material is a reinforced insulating material comprising tows of an elastomeric material and a reinforcing carrier embedded in the elastomeric material.

10. The sound wave absorbing laminated composite material structure according to claim 9, wherein: The support is a mesh of carbon fibers (CF) or glass fibers (GF).

11. A method for producing a sound-absorbing laminate composite structure according to any one of the preceding claims, the method comprising the steps of: a) providing at least three hybrid composite layups, b) stacking at least three hybrid composite plies, c) bonding at least three hybrid composite plies, and d) obtaining a laminated composite structure; Each hybrid composite layup is manufactured through the following steps: i) In the direction of longitude (d 经线 ) providing a plurality of tows of a first polymeric material, ii) In the latitude direction (d 纬线 ) providing a plurality of second polymeric material tows, each second polymeric material tow being interwoven with the plurality of first polymeric material tows, iii) in the direction of the meridian (d 经线 ) providing a plurality of absorbent material tows, each absorbent material tow being interwoven with the first polymeric material tow and the second polymeric material tow, Wherein, in the manufacture of the hybrid composite material ply, the first polymer material tow and the absorbent material tow are prestressed with a first stress and a second stress respectively, and the second polymer material tow is responsible for interweaving with the first polymer material tow and the absorbent material tow.

12. The method according to claim 11, wherein The step b) comprises the following steps: - stacking a first hybrid composite material layup in a first direction (d1), - stacking a second hybrid composite material ply with a second direction (d2) forming +45° with respect to said first direction (d1), - stacking a second hybrid composite ply with a third direction (d3) forming -45° with respect to said first direction (d1).

13. The method according to claim 11, wherein The step b) comprises the following steps: - stacking a first hybrid composite material layup in a first direction (d1), - stacking a second hybrid composite material ply with a second direction (d2) forming +45° with respect to said first direction (d1), - stacking a second hybrid composite layup in a third direction (d3), The first direction (d1) forms an angle of +45° with respect to the second direction (d2), and the third direction (d3) forms an angle of +135° with respect to the second direction (d2).

14. The method according to any one of claims 11 to 13, further comprising providing a plurality of carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP) composite plies, and laminating such carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP) composite plies in such a manner that the carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) composite plies are interposed between the hybrid composite plies.

15. An aircraft comprising an aircraft structure made from the sound-absorbing laminated composite material structure according to any one of claims 1 to 10.

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