Classifications

• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/005—Synthetic yarns or filaments
  • D04H3/009—Condensation or reaction polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/06—Fibrous reinforcements only
  • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
  • B29C70/088—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers and with one or more layers of non-plastics material or non-specified material, e.g. supports
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/28—Shaping operations therefor
  • B29C70/40—Shaping or impregnating by compression not applied
  • B29C70/42—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles
  • B29C70/46—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
  • B29C70/48—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM], e.g. by vacuum
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/28—Shaping operations therefor
  • B29C70/54—Component parts, details or accessories; Auxiliary operations, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing
  • B29C70/546—Measures for feeding or distributing the matrix material in the reinforcing structure
  • B29C70/547—Measures for feeding or distributing the matrix material in the reinforcing structure using channels or porous distribution layers incorporated in or associated with the product
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H13/00—Other non-woven fabrics
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/002—Inorganic yarns or filaments
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/002—Inorganic yarns or filaments
  • D04H3/004—Glass yarns or filaments
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/005—Synthetic yarns or filaments
  • D04H3/007—Addition polymers
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H3/00—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
  • D04H3/08—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating
  • D04H3/12—Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating with filaments or yarns secured together by chemical or thermo-activatable bonding agents, e.g. adhesives, applied or incorporated in liquid or solid form

Definitions

• the invention relates to the field of technical textiles used as reinforcements in molding processes.
• this type of complex is used in vacuum injection molding techniques, also known by the abbreviation RTM for "Resin Transfer Molding". It relates more particularly to a new complex design particularly suitable for charged resins.
• the RTM methods implement a step during which a textile reinforcement is impregnated with a resin intended to polymerize to harden this reinforcement.
• This resin is injected at one or more precise points, and must therefore flow inside the frame to distribute itself evenly.
• this reinforcement should have a high density of fibers.
• a high density is an obstacle to the creep of the resin.
• fillers ensuring this mechanization also makes it possible to reduce the density of the reinforcing layers, and therefore a reduction in the cost of the articles manufactured.
• These two types of resins therefore have a higher viscosity than the resins conventionally used in RTM techniques.
• These loaded resins can also include flame retardants which also increase its viscosity.
• a problem which the invention therefore proposes to solve is that of improving the creep capacity of the resin within a reinforcement of this type, while retaining satisfactory reinforcement properties, and a mechanical integrity of the assembly. .
• the invention therefore relates to a textile complex which can be used as a reinforcement in a part obtained by vacuum injection.
• this complex comprises a core layer formed of an openwork structure, having a spatial undulation, and which is formed of high tenacity yarns.
• This complex also includes at least one reinforcing layer, formed of a textile structure based on high tenacity fibers. This reinforcing layer comes into contact with a fraction of one of the faces of the core layer.
• the complex according to the invention comprises a central layer which is strongly perforated, in order to oppose a very limited resistance to the creep of the viscous resin.
• This central layer has a spatial undulation, that is to say it is in the form of a two-dimensional structure, but which has undergone deformations, so that it deviates from a plane of reference. It thus defines a free volume inside which the resin easily flows through it.
• These undulations of sinusoidal shape or equivalent, also give the central layer deformability possibly elastic, which allows it to collapse under the stresses generated in the molding operations.
• the associated reinforcement layer comes into contact with the latter only at the tops of the corrugations. This limitation of contact surface further promotes the deformation of the assembly.
• the openwork structure can have a spatial undulation in one or two directions depending on the type of use of the frame.
• the openwork structure of the core layer can advantageously be formed of a grid, composed of son of high tenacity, for example based on aramid, carbon, glass, or other fiber known for its tenacity, or even metallic wires
• the grid structure makes it possible to obtain a very large cutout, facilitating the creep of the resin.
• the grid structure is also appreciable for its deformation capacity due to the fact that the threads in the warp and weft directions can move relative to each other, as soon as their contact zones allow it.
• the grid may have weakening zones which make it possible to increase its deformability during installation in the mold.
• This embrittlement can be understood by a partial cut of the threads which compose it, that is to say a break of a fraction of filaments composing a thread, or even a break of some of the threads in localized areas.
• the threads of the perforated structure of the core layer can be coated with a resin which can be thermosetting or thermoplastic, since it has the property of not liquefying or too strongly softening. temperatures prevailing within the reinforcement during injection operations.
• the complex according to the invention can be used so that it comprises two reinforcing layers defining the volume of circulation and creep of the resin at the level of the perforated layer. These two reinforcing layers can be associated directly with the perforated central layer, during the manufacture of the complex. It is also possible to realize the complex by associating a layer on only one of the faces of the corrugated openwork structure. In this case, the creep volume of the resin can be defined by a second reinforcement layer subsequently associated with the complex, possibly even during the operation put into place in the mold.
• the reinforcing layer can be formed by different textile structures, in particular woven fabrics, or possibly knits, grids, multi-axial, mats or complexes.
• the reinforcing layers can also be formed by mats or nonwovens therefore made up of staple fibers, and having an isotropy.
• These reinforcing layers can also be themselves composite, and consist of several elementary layers, one of which for example can be used as an outer layer with improved flatness, in order to avoid the appearance on the molded article of the texture woven reinforcement if necessary.
• FIG. 1 is a summary perspective view of a complex according to the invention shown in an open configuration.
• Figure 2 is a cross-sectional view of the complex of Figure 1.
• Figure 1 illustrates a complex (1) mainly comprising a central layer (2) and two reinforcing layers (3,4).
• the reinforcement layer upper (3) is shown detached from the central layer (2) to facilitate understanding of the invention.
• the central layer (2) is formed of a grid structure comprising warp and weft of high tenacity yarns, which may be yarns of glass, carbon, aramid, or even liquid crystal fibers, or more generally high tenacity yarns.
• the grid is formed of threads present at a rate of 1 thread / cm, each having a titer of 600 tex.
• These wires (5,6) are coated with a layer of thermosetting material which can typically be based on epoxy resin, phenolic resin, or polyester or vinyl ester.
• These sheathing materials can advantageously include fillers intended to give the central layer (2) properties, for example mechanical or fire resistance properties.
• this sheathing of the grid wires has a chemistry similar or compatible to that of the resins which will be used subsequently during the molding operations.
• this central layer (2) has a spatial undulation.
• This spatial undulation gives a thickness to the layer (2) which is produced from an initially two-dimensional structure.
• the grid offers almost no resistance to the passage of resin, even very heavily loaded, and therefore of high viscosity.
• This central layer (2) is associated with a first reinforcing layer (3) which can be of very varied types. It can thus be, as already mentioned, a mat of glass threads or other high tenacity threads, or even woven structures or grid structures.
• These reinforcing layers have a capacity for retaining the resin, and can therefore consist of a plurality of stacked or mixed layers, which can have high reinforcing rates, and typically greater than 50%.
• the lower reinforcement layer (4) can be identical to the upper layer (3), but can also be produced in a different way, for example depending on the position it will occupy inside the injected part.
• the connection between the reinforcing layers and the central layer is made by bonding. This bonding can occur at the time of the thermoforming of the core, while the resins are still activated, or even in a subsequent operation after reactivation of the resins.
• the complex according to the invention has multiple advantages, and in particular: - it allows the flow of resin having a high viscosity, since its central layer imposes almost no resistance to the resin by its nature which is strongly openwork; - It has a very large deformation capacity due to the corrugated conformation of the central layer, which also has an appreciable degree of elasticity; - It provides mechanization of the part, thanks to the contribution of the core to the rigidity of the molded part.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Textile Engineering (AREA)
• Composite Materials (AREA)
• Mechanical Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Inorganic Chemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Laminated Bodies (AREA)
• Reinforced Plastic Materials (AREA)
• Injection Moulding Of Plastics Or The Like (AREA)
• Manufacturing Of Multi-Layer Textile Fabrics (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34945059

Family Applications (1)

Country Status (3)

Families Citing this family (2)

Family Cites Families (5)

• 2004
  • 2004-05-27 FR FR0451048A patent/FR2870860B1/fr not_active Expired - Fee Related
• 2005
  • 2005-05-24 EP EP05766605A patent/EP1748880A2/de not_active Withdrawn
  • 2005-05-24 WO PCT/FR2005/050352 patent/WO2005121430A2/fr not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events