Fibrous texture for composite material housing with local adaptation of elongation at break

Abstract

A fibrous texture for a composite material housing with local adaptation of elongation at break. A fibrous texture (100) having a three-dimensional weave between a plurality of warp yarn layers extending in a longitudinal direction (X) and a plurality of weft yarn layers extending in a lateral direction (Y), the warp yarns and the majority of the weft yarns being made of a first type of fiber, the fibrous texture further comprising a first portion (P1) and a second portion (P2). The second portion (P2) comprises a zone of increased elongation (ZA) extending over a determined width (1ZA) along the lateral direction (Y) and set back from the first and second lateral edges (101, 102) of the fibrous texture.The increased elongation zone (ZA) comprises weft yarns made of the first type of fibers and weft yarns made of a second type of fiber having a second elongation at break greater than the first type of fibers, the weft yarns present in the areas of the second portion located outside said at least one increased elongation zone being made of the first type of fibers. Figure for the abbreviation: Fig. 2.

Description

Title of the invention: Fibrous texture for a composite material housing with local adaptation of elongation at break. Technical field

[0001] The present invention relates to a fibrous texture which can be used, in particular but not exclusively, to form the fibrous reinforcement of an aircraft engine fan housing made of composite material. Previous technique

[0002] The manufacture of a composite material housing begins with the creation of a fibrous texture in the form of a strip. This fibrous texture is produced by three-dimensional weaving between a plurality of warp yarns and a plurality of weft yarns. The resulting fibrous texture is wound several times around a mold or tooling shaped like the housing to be produced and held between the mold and counter-mold segments to obtain a fibrous preform.

[0003] Once the fibrous preform has been made, i.e. at the end of the winding of the fibrous texture, the tooling carrying the fibrous preform is closed by counter-molds and then transported to an oven or furnace in which the densification of the preform by a matrix is ​​carried out, the matrix being able in particular to be obtained by injection and polymerization of a resin in the fibrous preform.

[0004] A blower housing performs three main functions, namely:

[0005] - to ensure the connection of engine parts to each other,

[0006] - define the air intake duct in the engine,

[0007] - ensure retention by retaining ingested debris inside the engine, or the blades or blade fragments projected by centrifugal force, in order to prevent them from passing through the casing and reaching other parts of the aircraft.

[0008] The first two functions are not very demanding in terms of mechanical properties but are continuously active. In contrast, the third function, although rarely used, is very demanding in terms of mechanical properties. In the event of blade failure, the blade fragments upon contact with the housing. Three types of stresses can then occur:

[0009] - A penetrating impact, very localized, generally at the axial position of the dawn. It causes perforation on the inner face and high local deformations on the outer face;

[0010] - A non-penetrating, relatively localized impact can occur downstream (and / or at (upstream) of the axial position of the blade. This impact generates local deformations raised on the inner and outer faces;

[0011] - A widespread wave of displacement / deformation that initiates from the impacts main, then propagates from one point to another in the casing.

[0012] To resist a penetrating impact, a solution is a localized thickening in the area of ​​this impact.

[0013] To resist a non-penetrating impact, one solution is a better elongation at break in the area of ​​that impact.

[0014] To resist a wave of deformation, local (or global) stiffening may be a solution.

[0015] Regarding the improvement of impact resistance, US2021164364 discloses the fabrication of a fibrous texture that improves the shear strength of a housing by using glass fibers among the carbon fibers in the fibrous texture. However, the use of glass fibers reduces the overall stiffness of the housing and, consequently, its resistance to a displacement / deformation wave.

[0016] Thus, there is a need to improve the resistance to a non-penetrating impact of a housing made of composite material while ensuring good resistance against a wave of displacement / deformation. Description of the invention

[0017] To this end, the invention proposes a fibrous texture having a band shape comprising an inner face and an outer face, the fibrous texture extending in a longitudinal direction over a determined length between a proximal part and a distal part and in a lateral direction over a determined width between a first lateral edge and a second lateral edge, the fibrous texture having a three-dimensional weave between a plurality of layers of warp yarns extending in the longitudinal direction and a plurality of weft layers extending in the lateral direction, the warp yarns and the majority of the weft yarns being made up of a first type of fibers having a first elongation at break,the fibrous texture further comprising a first portion extending along the longitudinal direction over a determined length from the proximal part and a second portion extending along the longitudinal direction over a determined length between the first portion and the distal part of said fibrous texture,

[0018] characterized in that the second portion comprises at least one zone with increased elongation extending over a determined width in the lateral direction and set back from the first and second lateral edges, and in that said at least one zone with increased elongation comprises weft yarns made of the first type of fibers and weft yarns made of a second type of fibers having a second elongation at break greater than the first elongation at break, the weft yarns present in the areas of the second portion located outside the area(s) with increased elongation being made up of the first type of fibers.

[0019] The fibrous texture is intended to be wound in several turns to form a fibrous reinforcement for a composite material housing. The first portion is intended to form the radially inner part of this fibrous reinforcement (first turn(s) of the winding). The second portion is intended to form the radially outer part of this fibrous reinforcement (last turn(s) of the winding).

[0020] The inventors have found that it is possible to locally improve the resistance of the casing to non-penetrating impact, for example with a detached blade, by a judicious placement of wires or strands made up of a second type of fiber having elongation at break greater than the elongation at break of the other wires or strands of the fibrous texture which are made up of a first type of fiber.

[0021] The other layers of warp and weft yarns or strands in the first portion but also in the areas of the second portion located outside the area(s) with increased elongation are made up of yarns or strands of the first type of fiber which has an elongation at break lower than that of the second type of fiber in order to maintain good rigidity in the first and second portions.

[0022] The fibrous texture of the invention therefore comprises one or more zones of increased elongation, the length of which along the direction of the warp yarns and the width along the direction of the weft yarns of which can be perfectly delimited within the fibrous texture. This makes it possible to form a composite material housing with one or more zones having specific mechanical properties that improve resistance to non-penetrating impact, without altering the mechanical properties of the other parts of the housing. The fibrous texture of the invention thus enables the production of composite material housings with improved resistance to non-penetrating impact while maintaining good resistance to displacement / deformation waves.

[0023] According to a feature of the fibrous texture of the invention, weft yarns in the area(s) of increased elongation on the outer face of the fibrous texture are made of the second type of fiber, while the weft yarns in the area(s) of increased elongation on the inner face of the fibrous texture are made of the first type of fiber. The insertion of weft yarns made of the second type of fiber on the outer face of the fibrous texture minimizes the occurrence of cracks in a housing using the fibrous texture as a fiber reinforcement because the tensile forces are primarily exerted on the outer face.

[0024] According to another characteristic of the fibrous texture of the invention, the quantity of threads the number of weft yarns made up of the second type of fibers present in the area(s) with increased elongation is between 10% and 50% of the number of weft yarns present in the area(s) with increased elongation.

[0025] According to one embodiment of the fibrous texture of the invention, the second portion of the fibrous texture comprises a number of warp yarn layers and weft yarn layers similar to the number of warp yarn layers and weft yarn layers of the first portion of said fibrous texture.

[0026] According to another embodiment of the fibrous texture of the invention, the area or areas with increased elongation in the second portion of the fibrous texture comprise a number of warp yarn layers and weft yarn layers greater than the number of warp yarn layers and weft yarn layers of the other parts of the second portion and the first portion of said fibrous texture.

[0027] The invention also relates to a fibrous preform for an aeronautical casing comprising a winding over several turns of a fibrous texture according to the invention, the first portion being located on the side of a radially internal face of the preform, and the second portion being located on the side of a radially external face of the preform.

[0028] The invention also relates to a gas turbine housing made of a composite material, comprising a fibrous reinforcement consisting of a fibrous preform according to the invention, and a matrix densifying the fibrous reinforcement. The housing may, in particular, be a gas turbine blower housing.

[0029] The invention also relates to an aeronautical gas turbine engine having a casing according to the invention.

[0030] The invention further relates to a method for manufacturing a fibrous texture by three-dimensional weaving between a plurality of layers of warp yarns extending in a longitudinal direction and a plurality of layers of weft yarns extending in the laterally direction, the warp yarns and the majority of the weft yarns being made up of a first type of fiber having a first elongation at break, the fibrous texture having a band shape comprising an inner face and an outer face, the fibrous texture extending in the longitudinal direction over a determined length between a proximal part and a distal part and in the lateral direction over a determined width between a first lateral edge and a second lateral edge,the process comprising weaving a first portion extending along the longitudinal direction over a determined length from the proximal part and a second portion extending along the longitudinal direction over a determined length between the first portion and the distal part of said fibrous texture,

[0031] characterized in that, during the weaving of the second portion of the fibrous texture, weft yarns made up of a second type of fiber having a second al elongation at break greater than the first elongation at break are inserted into at least one zone of increased elongation extending over a determined width in the lateral direction and set back from the first and second lateral edges of the fibrous texture, said at least one zone of increased elongation also comprising weft yarns made of the first type of fibers, the weft yarns present in the zones of the second portion located outside said at least one zone of increased elongation being made of the first type of fibers.

[0032] The process of the invention allows, as already described above, the creation of a fibrous texture comprising one or more zones of increased elongation, the length of which along the direction of the warp yarns and the width along the direction of the weft yarns of which can be precisely delimited within the fibrous texture. This makes it possible to form a composite material housing with one or more zones having specific mechanical properties that improve resistance to non-penetrating impact, without altering the mechanical properties of the other parts of the housing. The fibrous texture thus produced therefore allows the manufacture of composite material housings with improved resistance to non-penetrating impact while maintaining good resistance to displacement / deformation waves.

[0033] According to a feature of the process of the invention, during the weaving of the second portion of the fibrous texture, the weft yarns of the second type of fibers are inserted into the area or areas of increased elongation on the side of the external face of the fibrous texture, the weft yarns present in the area or areas of increased elongation present on the side of the internal face of the fibrous texture being made up of the first type of fibers.

[0034] According to another feature of the process of the invention, the quantity of weft yarns made up of the second type of fibers present in the area or areas with increased elongation is between 10% and 50% of the number of weft yarns present in said area or areas with increased elongation.

[0035] According to one embodiment of the process of the invention, during the weaving of the second portion of the fibrous texture, weft yarns of the first type of fibers are brought out of the fibrous texture before or in the area(s) of increased elongation while the weft yarns of the second type of fibers are inserted into the fibrous texture in the area(s) of increased elongation, weft yarns of the first type of fibers being reintroduced into or after the area(s) of increased elongation.

[0036] According to another embodiment of the process of the invention, the area(s) with increased elongation in the second portion of the fibrous texture are woven with a greater number of warp yarn layers and weft yarn layers than the number of warp yarn layers and weft yarn layers in the other parts of the second portion and the first portion of said fibrous texture. Brief description of the drawings

[0037] [Fig. 1] Fig. 1 is a schematic perspective view of a loom showing the three-dimensional weaving of a fibrous texture,

[0038] [Fig.2] Fig.2 is a schematic perspective view of a fibrous texture according to one embodiment of the invention,

[0039] [Fig.3] [Fig.3] is a cross-section taken at the level of an area of ​​increased elongation of the fibrous texture of [Fig.2] and showing a weave pattern according to an embodiment of the invention,

[0040] [Fig.4] [Fig.4] is a cross-section taken at the level of an area of ​​increased elongation of the fibrous texture of [Fig.2] and showing a weave pattern according to another embodiment of the invention,

[0041] [Fig.5] Fig.5 is a schematic perspective view showing the winding of a fibrous texture onto a shaping tool,

[0042] [Fig.6] [Fig.6] is a half axial cross-sectional view of a preform of a housing obtained by winding a fibrous texture as shown in [Fig.5],

[0043] [Fig.7] The [Fig.7] is a cross-sectional view showing the positioning of injection sectors on the preform of the housing of the [Fig.6],

[0044] [Fig.8] The [Fig.8] is a perspective view of an aircraft engine according to one embodiment of the invention. Description of the implementation methods

[0045] The invention applies generally to fibrous textures intended for the manufacture of housings made of composite material, these housings comprising a barrel or a ferrule with annular flanges at their ends.

[0046] As shown in [Fig.1], a fibrous texture 100 is produced in a known manner by weaving using a jacquard type loom 5 on which a bundle of warp yarns or strands 20 has been arranged in a plurality of layers, the warp yarns being linked by weft yarns or strands 30.

[0047] The fibrous texture is achieved by three-dimensional weaving. "Three-dimensional weaving" or "3D weaving" refers to a weaving method in which at least some of the weft yarns interlock with warp yarns over several layers of warp yarns, or vice versa. The fibrous texture may have an interlock weave. "Interlock" weaving refers to a weave in which each layer of weft yarns interlocks with several layers of warp yarns, with all yarns in the same weft column having the same movement within the plane of the weave. Other weave structures are possible.

[0048] As illustrated in [Fig. 2], the fibrous texture 100 has a band-like shape comprising an inner face Fl and an outer face F2. The fibrous texture 100 extends lengthwise in a longitudinal direction X corresponding to the direction of the warp yarns or strands 20 and widthwise or transversely in a lateral direction Y between a first lateral edge 101 and a second lateral edge 102, the lateral direction Y corresponding to the direction of the weft yarns or strands 30. The fibrous texture extends longitudinally over a determined length Li00 in the X direction between a proximal portion 110 intended to form the beginning of the winding of a fibrous preform on a forming tool and a distal portion 120 intended to form the end of the winding of the fibrous preform. The fibrous texture extends transversely over a determined width l100 in the Y direction between the first and second lateral edges 101 and 102.

[0049] The length Li00 of the fibrous texture 100 is determined as a function of the circumference of the tooling or shaping mold so as to allow the realization of a determined number of turns of the fibrous texture, for example four turns.

[0050] The fibrous texture 100 comprises a first portion PI and a second portion P2. The first portion PI extends along the longitudinal direction X for a predetermined length LPi from the proximal part 110 and the second portion P2. The second portion P2 extends along the longitudinal direction X for a predetermined length LP2 between the first portion PI and the distal part 120 of the fibrous texture 100. The first portion PI is intended to form the first part of the winding that constitutes the fibrous reinforcement of the housing, while the second portion P2 is intended to form the second part of the winding that constitutes the fibrous reinforcement of the housing (the radially internal and external parts of this winding, respectively, see [Fig. 7], which shows the radial direction R). The length LP2 of the second portion P2 is preferably defined so as to correspond to the last turn of the winding on the forming tool or mold ([Fig. 7]).

[0051] According to the invention, the second portion P2 of the fibrous texture 100 comprises an increased elongation zone ZA extending over a length LZA along the longitudinal direction X and over a width 1ZA determined along the lateral direction Y and set back from the first and second lateral edges 101 and 102 of the fibrous texture. In the example described here, the length ZLA of the increased elongation zone ZA is equal to the length LP2 of the second portion P2. The length ZLA of the increased elongation zone ZA is preferably less than or equal to the length LP2 of the second portion P2 so as to be present only at the last winding turn or outer turn of the fibrous reinforcement. The width 1ZA is defined according to the width of the area of ​​interest of the final casing on which a locally higher elongation break is desired. The second portion P2 comprises a first zone 130 extending along the lateral direction Y between the first lateral edge 110 and the zone with increased elongation ZA and a second zone 140 extending along the lateral direction Y between the zone with increased elongation ZA and the second lateral edge 102. The first and second zones 130 and 140 correspond to the part of the second portion P2 located outside the zone with increased elongation.

[0052] The first portion PI and the first and second zones 130 and 140 of the second portion P2 of the fibrous texture comprise warp yarns or strands and weft yarns or strands made of a first type of fiber having a first elongation at break. The warp yarns and weft yarns made of the first type of fiber are intended to impart stiffness to the casing and may be made, in particular, of carbon fibers.

[0053] According to the invention, the increased elongation zone comprises Ti weft yarns made of the first type of fibers and T2 weft yarns made of a second type of fiber having a second elongation at break greater than the first elongation at break. The T2 weft yarns may, in particular, be made of glass fibers, basalt fibers, or aramid fibers.

[0054] Thus, during the weaving of the second portion of the fibrous texture P2, weft yarns T2 made up of the second type of fibers are inserted at the level of the zone with increased elongation ZA.

[0055] Fig. 3 illustrates a plane of the interlock weave structure in the second portion P2 of the fibrous texture 100 located at the level of the increased elongation zone ZA according to one embodiment of the invention.

[0056] The example of the weave pattern illustrated in [Fig. 3] comprises eight warp layers C ci to CC8 and six weft layers Cn to CT6. Usable interlock weave patterns are described in document WO 2006 / 136755.

[0057] In the illustrated example, all the warp yarns of the warp yarn layers CCi to CCs are Ci yarns made up of the first type of fibers. The weft yarns of the weft yarn layers CT4 to CT6 are also Ti yarns made up of the first type of fibers which extend over the entire width liOo of the fibrous texture 100, that is to say in the zones 130 and 140 as well as in the zone with increased elongation ZA on the side of the inner face Fl of the fibrous texture.

[0058] In accordance with the invention and as illustrated in [Fig. 3], during the weaving of the second portion P2 of the fibrous texture 100, weft yarns T2 made of the second type of fiber having a second elongation at break greater than that of the first type of fiber are inserted into an increased elongation zone ZA. More specifically, the weft yarns Ti of the weft yarn layers CTi to CT3 present in the second zone 140 are removed from the fibrous texture before the increased elongation zone ZA in order to be replaced by weft yarns T2 inserted at the beginning of the zone with increased elongation ZA and woven with warp yarns following the weave structure. The weft yarns T2 inserted in the layer of weft yarns Cn to CT3 are taken out of the fibrous texture at the end of the zone with increased elongation ZA in order to be replaced by weft yarns Ti inserted at the beginning of the first zone 130 and woven with warp yarns following the weave structure.

[0059] By replacing some Ti weft yarns with T2 weft yarns in a determined part of the fibrous texture, a zone with increased elongation is obtained locally by the presence of T2 weft yarns without an increase in the thickness of the fibrous texture.

[0060] [Fig.4] illustrates a plane of the interlock weave in the second portion P2 of the fibrous texture 100 located at the level of the increased elongation zone ZA according to another embodiment of the invention which differs from the embodiment of [Fig.3] in that the second portion P2 of the fibrous texture 100 is woven with a number of warp yarn layers and weft yarn layers greater than the number of warp yarn layers and weft yarn layers of the other parts of the second portion P2 and the first portion PI of said fibrous texture.

[0061] More specifically, the example of the weave pattern illustrated in [Fig. 4] comprises, within the entire fibrous texture 100, i.e., in the first and second portions PI and P2, eight warp layers Cci to CCs and six weft layers CTi to CT6-

[0062] In the illustrated example, all the warp yarns in the warp yarn layers CCi to CCs are Ci yarns made of the first type of fibers. The weft yarns in the weft yarn layers CTi to CT6 are also Ti yarns made of the first type of fibers, which extend over the entire width l100 of the fibrous texture 100, i.e., in zones 130 and 140 as well as in the zone with increased elongation ZA.

[0063] According to the invention and as illustrated in [Fig.4], during the weaving of the second portion P2 of the fibrous texture 100, additional weft yarn layers CT7 to CT9 comprising weft yarns T2 made of the second type of fiber having a second elongation at break greater than that of the first type of fiber are woven with warp yarns Ci belonging to additional warp yarn layers Cc9 to CCn in an area with increased elongation ZA.

[0064] In this case, the fibrous texture 100 has an extra thickness at the level of the increased elongation zone ZA present in the second portion P2. The presence of weft yarns T2 in a part of the extra thickness of the fibrous texture 100 makes it possible to locally form an increased elongation zone while retaining warp yarns Ci and weft yarns Ti made up of the first type of fibers in the warp yarn layers C ci to Ces and Cn to CT6 in the whole of the fibrous texture.

[0065] We have just described examples in which the fibrous texture has an armor of Interlock weave with eight layers of warp yarns and six layers of weft yarns (excluding the additional warp and weft yarn layers shown in [Fig. 4]). However, the invention remains within the scope of this invention when the number of warp and weft layers differs, or when the fiber texture exhibits a weave structure other than an interlock weave.

[0066] According to a particular feature, the weft yarns T2 made up of the second type of fibers are preferably present on the side of the external face F2 of the fibrous texture in the area of ​​increased elongation while the weft yarns Ti made up of the first type of fibers are present on the side of the internal face Fl of the fibrous texture in said area of ​​increased elongation.

[0067] According to another particular feature, the quantity of T2 weft yarns made up of the second type of fibers present in the increased elongation zone is between 10% and 50% of the number of weft yarns present in said increased elongation zone.

[0068] As illustrated in [Fig. 5], a fibrous housing reinforcement is formed by winding the fibrous texture 100 described previously onto a mandrel 50, the fibrous reinforcement constituting a complete tubular fibrous preform of a one-piece housing. For this purpose, the mandrel 50 has an external surface 51 whose profile corresponds to the internal surface of the housing to be produced. The mandrel 50 also includes two flanges 52 and 53 to form portions of the fibrous preform 62 and 63 corresponding to the flanges of the housing (the flanges 62 and 63 are visible in [Fig. 6]). The turn(s) located radially towards the inside of the preform correspond to the first portion P1 of the fibrous texture, and the turn(s) located radially towards the outside of the preform correspond to the second portion P2 of the fibrous texture. In the example described here and as illustrated in [Fig. 6], the fibrous reinforcement is formed by winding the fibrous texture 100 onto a mandrel 50.[7], the preform 60 comprises four turns of fibrous texture 100, the first three turns being formed by the first portion PI while the last turn corresponding to the outer layer of the preform is formed by the second portion P2 containing the area with increased elongation.

[0069] Figure 6 shows a cross-sectional view of the fibrous preform 60 obtained after winding the fibrous texture 100 in several layers onto the mandrel 50. The number of layers or turns depends on the desired thickness and the thickness of the fibrous texture. It is preferably at least 2. According to the invention, the fibrous preform 60 includes the increased elongation zone obtained by inserting weft yarns of the second type of fiber having a greater elongation at break than the other yarns of the preform. The axial length along an axial direction Da of the increased elongation zone is defined as a function of the area of ​​interest where it is desired to improve resistance to a non-penetrating impact.

[0070] The fibrous preform 60 is then densified by a matrix.

[0071] The densification of the fibrous preform consists of filling the porosity of the preform, in all or part of its volume, with the material constituting the matrix.

[0072] The matrix can be obtained in a manner known per se by the liquid process. The liquid process consists of impregnating the preform with a liquid composition containing an organic precursor of the matrix material. The organic precursor is usually in the form of a polymer, such as a resin, possibly diluted in a solvent. The fibrous preform is placed in a mold that can be sealed tightly with a cavity having the shape of the final molded part. As illustrated in [Fig. 7], the fibrous preform 60 is placed here between a plurality of sectors 54 forming a counter-mold and the mandrel 50 forming a support, these elements having respectively the external and internal shapes of the housing to be produced. Then, the liquid matrix precursor, for example a resin, is injected throughout the cavity to impregnate the preform.

[0073] The transformation of the precursor into an organic matrix, namely its polymerization, is carried out by heat treatment, generally by heating the mold, after removal of any solvent and crosslinking of the polymer, the preform always being held in the mold, which has a shape corresponding to that of the part to be produced. The organic matrix can be obtained, in particular, from epoxy resins, such as, for example, the high-performance epoxy resin sold, or from liquid precursors of carbon or ceramic matrices.

[0074] The densification of the fibrous preform can be achieved by the well-known resin transfer molding (RTM) process. According to the RTM process, the fibrous preform is placed in a mold having the shape of the housing to be produced. A thermosetting resin is injected into the internal space defined between the rigid material part and the mold, which includes the fibrous preform. A pressure gradient is generally established in this internal space between the point where the resin is injected and the resin discharge ports in order to control and optimize the impregnation of the preform by the resin.

[0075] The resin used can be, for example, an epoxy resin. Resins suitable for RTM processes are well known. They preferably have a low viscosity to facilitate their injection into the fibers. The choice of temperature class and / or the chemical nature of the resin is determined according to the thermomechanical stresses to which the part must be subjected. Once the resin has been injected throughout the reinforcement, it is polymerized by heat treatment in accordance with the RTM process.

[0076] After injection and polymerization, the part is demolded. The part is then trimmed to remove excess resin and the chamfers are machined to obtain a crankcase 810 exhibiting a form of revolution as illustrated in [Fig.8].

[0077] The casing 810 shown in [Fig. 8] is a casing for a fan of an aircraft gas turbine engine 80. Such an engine, as shown schematically in [Fig. 7], comprises, from upstream to downstream in the direction of the gas flow, a fan 81 located at the engine inlet, a compressor 82, a combustion chamber 83, a high-pressure turbine 84, and a low-pressure turbine 85. The engine is housed within a casing comprising several parts corresponding to different engine components. Thus, the fan 81 is surrounded by the casing 810.

[0078] In addition, the housing 810 has a local annular zone 811 corresponding to the zone with increased elongation ZA made in the fibrous texture and which has improved resistance to non-penetrating impact.

[0079] In the example described here, the fibrous texture used to form the fibrous reinforcement of the composite material housing includes a zone with increased elongation. However, the fibrous texture may include several such zones depending on the requirements of the final part.

Claims

Demands

1. Fibrous texture (100) having a band shape comprising an inner face (F1) and an outer face (F2), the fibrous texture extending in a longitudinal direction (X) over a determined length (L1) between a proximal portion (110) and a distal portion (120) and in a lateral direction (Y) over a determined width (110) between a first lateral edge (101) and a second lateral edge (102), the fibrous texture having a three-dimensional weave between a plurality of layers of warp yarns (20) extending in the longitudinal direction and a plurality of layers of weft yarns (30) extending in the laterally direction, the warp yarns (C1) and the majority of the weft yarns (TJ) being made up of a first type of fiber having a first elongation at break,the fibrous texture further comprising a first portion (PI) extending along the longitudinal direction over a determined length (Lpi) from the proximal part (110) and a second portion (P2) extending along the longitudinal direction over a determined length (LP2) between the first portion and the distal part of said fibrous texture, characterized in that the second portion (P2) comprises at least one zone of increased elongation (ZA) extending over a determined width (1ZA) along the lateral direction (Y) and set back from the first and second lateral edges (101, 102) and in that said at least one zone of increased elongation (ZA) comprises weft yarns (TJ) made up of the first type of fibers and weft yarns (T2) made up of a second type of fibers having a second elongation at break greater than the first elongation at break,the weft yarns (Ti) present in the areas of the second portion located outside of said at least one area of ​​increased elongation being made up of the first type of fibers.

2. Fibrous texture according to claim 1, wherein weft yarns (T2) present in said at least one area with increased elongation on the side of the outer face (F2) of the fibrous texture (100) are made of the second type of fibers, the weft yarns (TJ) present in said at least one area with increased elongation present on the side of the inner face (Fl) of the fibrous texture (100) being made of the first type of fibers.

3. Texture according to claim 1 or 2, wherein the quantity of yarns weft (T2) made up of the second type of fibers present in said at least one increased elongation zone (ZA) is between 10% and 50% of the number of weft yarns present in said at least one increased elongation zone.

4. Texture according to any one of claims 1 to 3, wherein the second portion (P2) of the fibrous texture (100) comprises a number of warp yarn layers (Cci-Ccs) and weft yarn layers (CTi-CT6) similar to the number of warp yarn layers and weft yarn layers of the first portion (PI) of said fibrous texture.

5. Texture according to any one of claims 1 to 3, wherein said at least one increased elongation zone (ZA) in the second portion (P2) of the fibrous texture (100) comprises a number of warp yarn layers (Cci-Ccu) and weft yarn layers (Cn-Crç) greater than the number of warp yarn layers (Cci-Ccs) and weft yarn layers (CTi-CT6) of the other parts of the second portion (P2) and the first portion (PI) of said fibrous texture.

6. A fibrous preform (60) for an aeronautical casing (810) comprising a multi-turn winding of a fibrous texture (100) according to any one of claims 1 to 5, the first portion (PI) being located on the side of a radially internal face of the preform, and the second portion (P2) being located on the side of a radially external face of the preform.

7. Gas turbine housing (810) of a composite material, comprising a fibrous reinforcement consisting of a fibrous preform (60) according to claim 6, and a matrix densifying the fibrous reinforcement.

8. Carter (810) according to claim 7, wherein said housing is a gas turbine blower housing.

9. Aeronautical gas turbine engine (80) having a casing (810) according to claim 7 or 8.

10. A method for manufacturing a fibrous texture (100) by three-dimensional weaving between a plurality of layers of warp yarns (20) extending in a longitudinal direction (X) and a plurality of layers of weft yarns (30) extending in the lateral direction (Y), the warp yarns (Ci) and the majority of the weft yarns (Ti) being made of a first type of fiber having a first elongation at break, the fibrous texture (100) having a band shape comprising an inner face (F1) and an outer face (F2), the texture fibrous extending in the longitudinal direction (X) over a determined length (L100) between a proximal part (110) and a distal part (120) and in the lateral direction (Y) over a determined width (L100) between a first lateral edge (101) and a second lateral edge (102), the method comprising weaving a first portion (P1) extending along the longitudinal direction over a determined length (LP1) from the proximal part (110) and a second portion (P2) extending along the longitudinal direction over a determined length (LP2) between the first portion and the distal part of said fibrous texture, characterized in that, during the weaving of the second portion (P2) of the fibrous texture (100),weft yarns (T2) made of a second type of fiber having a second elongation at break greater than the first elongation at break are inserted into at least one increased elongation zone (ZA) extending over a determined width (Iza) along the lateral direction (Y) and set back from the first and second lateral edges (101, 102) of the fibrous texture, said at least one increased elongation zone (ZA) also comprising weft yarns (Ti) made of the first type of fiber, the weft yarns (Ti) present in the zones of the second portion located outside said at least one increased elongation zone being made of the first type of fiber.

11. A method according to claim 10, wherein, during the weaving of the second portion (P2) of the fibrous texture (100), the weft yarns (T2) of the second type of fibers are inserted into said at least one zone with increased elongation (ZA) on the side of the outer face (F2) of the fibrous texture (100), the weft yarns (Ti) present in said at least one zone with increased elongation present on the side of the inner face of the fibrous texture being made up of the first type of fibers.

12. A method according to claim 10 or 11, wherein the quantity of weft yarns (T2) made up of the second type of fibers present in said at least one increased elongation zone (ZA) is between 10% and 50% of the number of weft yarns present in said increased elongation zone.

13. A procedure according to any one of claims 10 to 12, wherein, during the weaving of the second portion (P2) of the fibrous texture (100), weft yarns (Ti) of the first type of fibers are brought out of the fibrous texture before or within said at least one elongation zone increased (ZA) while weft yarns (T2) of the second type of fiber are inserted into the fibrous texture in said at least one zone with increased elongation, weft yarns (TJ) of the first type of fiber being reintroduced into said at least one zone with increased elongation or after said at least one zone with increased elongation.

14. A method according to any one of claims 10 to 12, wherein said at least one increased elongation zone (ZA) in the second portion (P2) of the fibrous texture (100) is woven with a number of warp yarn layers (Cci-Ccn) and weft yarn layers (CTi-CT9) greater than the number of warp yarn layers (CcrCcs) and weft yarn layers (CTi-CT6) of the other parts of the second portion (P2) and the first portion (PI) of said fibrous texture.