Abstract: A beam of fiber-reinforced curable thermosetting composite material is preliminarily assembled in an uncured condition. The beam is placed between two forming tools, namely a lower and an upper tool, shaped in such a way as to give the lower and upper flanges a predetermined shape, at least one of the flanges having a non-rectilinear profile viewed in a longitudinal vertical plane. Two longitudinally elongate rigid inserts are placed between the flanges at the sides of the web and are covered in respective airtight tubular bags. The spaces between the upper tool and the lower tool on the two opposite longitudinal sides are sealed. The open opposite ends of the tubular bags are also sealed in such a manner that the pressure applied in an autoclave during the step of curing causes the tubular bags to swell and presses them against the two opposite faces of the web and against the flanges of the beam. On completion of curing, the upper forming tool is removed and the inserts are extracted sideways.

Abstract: Pultrusion methods and apparatus for manufacturing a profiled preform or FRP-component with cross-sectional segments that extend angularly to one another from a plurality of semifinished products in a quasi-continuous process, where: at least one multilayer semifinished product arrangement [of a multilayer semifinished product arrangement] is dispensed from a dispenser unit in order to manufacture the preform, with the multilayer semifinished product arrangement dispensed from the dispenser unit being fed to the forming device and including a combination of several webs of semifinished reinforcement fiber layers and at least one resin film; the semifinished product arrangement is guided through a forming device and at least one cross-sectional segment of the semifinished product arrangement is angled in order to form an angle profile, with the semifinished product arrangement being compressed in a pressing device, optionally after a hardening process, and with a longitudinal section of the preform or the comp

Abstract: Methods and apparatus for vacuum infusing resin into a fabric preform within a mold. The methods comprise increasing permeability in a selected region, such as by deploying a VIPR chamber in a location corresponding to the resin injection port corresponding to the resin flow front furthest from the mold vent or a location identified by predictive modeling as best to achieve a desired flow front geometry. Suitable apparatus comprise a VIPR chamber, an image detector for detecting resin flow fronts, a processor programmed to identify a desired location to deploy the VIPR chamber, and an automatic positioner for moving the VIPR chamber to the identified location.

Abstract: The present invention relates to a three dimensionally fiber-reinforced riser and to the unitary or single-step methods of making the same. In one embodiment (a cross bow riser for example), the riser has an interior support with opposed side members and a front brace. The front brace has a depression centrally located therein. Two side ribs are also provided for structural support. Two pockets each optionally having a divider wall defining a top and bottom section are provided for receiving respective top and bottom pieces of a split limb, when a split limb is used. The riser can be made of a composite material having fibers aligned there within in the directions of the highest stresses for enhancing the structural strength of the riser. Other bow parts or components can likewise be made via composite material as well.

Abstract: A mandrel having an out-of-plane curvature and a corresponding in-plane change in mandrel geometry is used to fabricate substantially wrinkle-free, fiber reinforced stiffeners having an out-of-plane curvature.

Abstract: The present invention relates to a method of fabricating a composite part presenting an integral structure of composite material comprising at least one reinforcing layer based on reinforcing fibers, fabrics, or textiles, and at least one impregnation matrix, the method consisting in assembling the integral structure, in placing said integral structure in a mold, in impregnating said integral structure with the impregnation matrix by injection or infusion, and in solidifying said impregnated integral structure by raising it to a determined temperature, the method being characterized in that it consists in: using at least two distinct primary parts for making up the integral structure; placing a thermoplastic sheet on at least one of the primary parts so as to make the interface between said primary parts once they are assembled together.

Abstract: A method is presented for stably, highly, and efficiently producing a three-dimensional molded article of a fiber-reinforced composite material having a three-dimensional shape, uniform quality, and free from wrinkles by press molding a plurality of prepregs cut out in a predetermined shape and also to a molded article.

Abstract: During the cooking of a composite component including layers of fibers embedded into a matrix, a superficial pressure is exerted. This superficial pressure generates a deformation that causes local contacts of fibers of at least two layers without damaging these fibers. As a result, when an electrical current is applied on a side of the composite component, such as during a lightning strike or a short circuit, the added local contacts enable the electric current to flow along multiple fibers in the composite component, thereby avoiding significant spikes in temperature.

Abstract: A method for joining fittings to a composite sandwich shell edge includes laying up an inner facesheet and positioning a wrapped flute mandrel on top; applying a layer of adhesive on the inner facesheet and positioning spacer-supported fittings on top; applying adhesive over the co-bonded fittings and laying up an outer facesheet forming an assembly; curing the assembly under heat and pressure; removing the fittings by first collapsing the spacers and removing the flute mandrel; placing an adhesive layer on the fittings with collapsible spacers inserted therein; reinserting the fittings between the inner and outer facesheets and effecting bonding and curing; and removing the spacers from the fittings by collapsing the spacers.

Abstract: A method of forming a hole in a composite panel includes positioning a first fiber sheet on a layup table, where the layup table has a forming tool extending outward from a portion of the table, and the fiber sheet includes a plurality of fibers oriented along a first common direction. The method further includes extending the forming tool through the first fiber sheet such that a subset of the plurality of fibers are displaced about the forming tool: applying a resin to the sheet of fibers; pre-curing the resin to form a pre-preg part defining a hole about the forming tool; and removing the pre-preg part from the layup table.

Abstract: A method of integrally forming a composite rib structure includes positioning a first fiber sheet on a pre-preg mold, the pre-preg mold including a first channel and a second channel separated by a wedge-shaped protrusion, and the fiber sheet including a plurality of fibers oriented along a first common direction. The method further including extending the wedge-shaped protrusion through the first fiber sheet such that a subset of the plurality of fibers are displaced about the protrusion and into each of the respective first channel and second channel; applying a resin within each of respective first channel and second channel to the plurality of fibers; pre-curing the resin to form a pre-preg rib structure within the channels; and removing the pre-preg rib structure from the pre-preg mold.

Abstract: There is provided a porous, carbon-containing preform, including a body (CL) of unidirectional carbon fiber fabrics (C1), and a friction layer (FL) of randomly-arranged-carbon-fiber fabrics (F1), combined with the body (CL) by a needle-punching operation. According to the present invention, it is by the needle-punching operation that the friction layer (FL) of the randomly-arranged-carbon fiber fabric (F1) is formed on the body (CL) of the unidirectional carbon fiber fabric (C1) and the friction layer (FL) of the randomly-arranged-carbon-fiber (F1) is cross-linked to the body (CL) of the unidirectional carbon fiber fabric (C1) in producing the porous, carbon-containing preform.

Abstract: A pre-form CMC cavity and method of forming pre-form CMC cavity for a ceramic matrix component includes providing a mandrel, applying a base ply to the mandrel, laying-up at least one CMC ply on the base ply, removing the mandrel, and densifying the base ply and the at least one CMC ply. The remaining densified base ply and at least one CMC ply form a ceramic matrix component having a desired geometry and a cavity formed therein. Also provided is a method of forming a CMC component.

Abstract: A method for making parts with variable thickness corners and parts with variable thickness corners are disclosed. The method includes laying up multiple plies to form a tailored blank, associating the blank with a convex and concave die, and applying pressure and heat so that material from at least one of the plies migrates towards a voided corner area formed between the dies.

Abstract: A method of fabricating an element (25) out of composite material, the element comprising three arms (22, 23, 24) arranged in a triangle. The method comprises the operations of: fabricating a three-dimensionally woven preform from reinforcing fibers and including through slots defining two arms (22, 23) and two half-arms that are all parallel and contiguous in pairs, each arm (22, 23) having one end whereby it is connected to a half-arm and another end whereby it is connected to the other arm (22, 23); shaping the preform by deploying it and by uniting its two half-arms in order to give it a triangle configuration; securing together the half-arms by stitching with reinforcing fibers; and injecting resin into the preform and polymerizing the resin.

Abstract: A method of fabricating a reinforced thermoplastic composite part comprises moving a laminate of reinforcing fibers embedded in a thermoplastic matrix for sequential operations through a heating station and then a forming station. The heating station is used to soften the thermoplastic matrix in a portion of the laminate while the forming station is used to impart a geometry to a portion of the laminate whose thermoplastic matrix had just been softened. The softening and the forming are performed simultaneously on different portions of the laminate.

Abstract: In accordance with the method, an inside layer of a fuselage section skin made from first fibers is placed on a manufacturing surface, the first fibers being placed in one or more first fiber directions. On the inside layer, a stiffening structure is formed from stiffening fibers, the stiffening fibers being placed in one or more stiffening fiber directions. An outside layer of the fuselage section skin, comprising fourth fibers, is placed on the stiffening structure formed from stiffening fibers, the fourth fibers being placed in one or more fourth fiber directions. The stiffening structure is designed and developed in such a way that the fuselage section does not require an additional stiffening structure, is connected with the fuselage section skin, and comprises the inside layer, the stiffening structure, and the outside layer; in particular, an additional stiffening structure in the form of stringers and frames is not required.

Abstract: A method of vacuum-assisted RTM includes disposing a resin distribution medium on one surface of a reinforcing-fiber substrate, covering the whole with a bag material, reducing the pressure inside the bag material, and injecting a resin into the resin distribution medium to distribute the resin substantially in in-plane directions and then impregnate the resin into the reinforcing-fiber substrate in the thickness direction.

Abstract: A fiber reinforced part is formed from a compression molded thermoplastic resin reinforced with individual fibers of differing lengths randomly oriented substantially throughout the part.

Abstract: The present invention discloses a method of producing and application for a projectile resistant matrix that allows for manufacture of low weight projectile resistant armor trauma shields without metal or ceramic plates using projectile resistant textiles encapsulated in a composite matrix through use of injection molding process or spray-on technique as constituents of the projectile resistant trauma shield without metal or ceramic plates of the present invention.

Abstract: A method for producing a closed-section portion of an aircraft wherein a strain gauge is glued on a first face of a flat tape that, in turn, is fastened on a face of a tool comprising a rigid elongated body covered by an extensible sack. The tool supporting the tape is arranged in a cavity of an aircraft structure. A vacuum is then created to obtain the expansion of the vacuum sack and perform the pressure gluing of the tape onto a wall of said cavity. The tool is subsequently extracted from the cavity. Upon conclusion of these operations, the tape is integrally fastened onto a wall of the cavity so that any deformation applied to this wall is transmitted to said strain gauge.

Abstract: A process for producing a fiber reinforced resin which comprises placing at least a reinforcing fiber substrate in a cavity of a mold, injecting a resin into the cavity, and curing the resin, characterized in that a substrate for forming a skin layer, and a resin distribution medium, which is located between the substrate for forming the skin layer and the reinforcing fiber substrate and in which the ratio of the coefficient of impregnation thereof to that of the substrate for forming the skin layer is 1.5-10, are disposed on at least one surface of the reinforcing fiber substrate via an interlayer having a cover factor of 90%-100% and comprising at least one woven fabric. The process diminishes pinhole generation in the skin layer in RTM, and can reduce the necessity of a repair step in, e.g., a painting step as a later step, thereby improving productivity.

Abstract: The present invention relates to a composite article 801, wherein the article has a longitudinal direction L and a transversal direction T, the article 80 comprises a stack of plies wherein one ply is a bottom ply and one ply is a top ply, most of or all of the plies comprise fibres, and the article comprises a plurality of plies having fibres substantially in the orthogonal direction 810 to the longitudinal direction L of the article 801 and the stack further comprises a plurality of plies having fibres substantially in the same direction 811 as the longitudinally direction L of the article 801 and/or a plurality of plies having fibres in the diagonal direction (812, 813, 815, 816, 817, 818) of the longitudinal direction (L) of the article (801), wherein at least one of the ply/plies having fibres substantially in the orthogonal direction 810 to the longitudinal direction L of the article 801 comprise fibres that are stiffer than the fibres in the other plies which have less stiff fibres.

Abstract: Composite pre-forms are molded at high pressure to form composite parts that can be used in place of metal-based high performance parts, such as the outlet guide vanes found in turbofan jet engines. The composite pre-forms include two different fiber orientations that are co-molded in a resin matrix at high pressures to provide composite outlet guide vanes and other high performance parts. Chambers within the composite part are optionally formed during molding of the pre-form at high pressures.

Abstract: A composite component, such as an aerofoil component for a gas turbine engine, comprises a body and a platform which are formed from respective body and platform preforms. The body preform includes fibers which are directed laterally of the preform, forming a cavity in the end of the preform. The platform preform includes a projection constituting a deltoid filler which is received in the cavity. The projection includes a 3D woven structure of reinforcement fibers so that the cavity is occupied by fibers to give the platform a generally uniform volume fraction. A further platform preform fits over the body preform so that the lateral fibers are sandwiched between the platform preforms.

Abstract: A method for manufacturing rigid panels made of a composite material requires a caul sheet having a smooth surface that is formed with a plurality of grooves. A first layer of the composite material is laid on the caul sheet, and is cut to create flaps that extend into the respective grooves. Strips of composite material are then placed along the edges of the groove to extend and overlap each other in the groove. Next, a unidirectional ply is placed along the length of the groove, and this combination is then covered with a second layer of the composite material. Together, the combination of the first and second layers, the strips and the unidirectional ply are co-cured to create a rigid panel with integral stiffening members.

Abstract: An apparatus and method of manufacturing a skeg protector to cover a motorboat skeg to prevent damage to the skeg and to the propellers. The SkegProtector™ apparatus is made of a composite of non-stainless steel woven material of high material strength and durability, such as carbon fiber, Kevlar®, fiberglass, titanium, and polyethylene fiber. It is affixed over the skeg using marine grade underwater adhesive, and without installing bolts or other mechanical means to secure it. Methods of manufacture comprise the use of curing using a heated platen press on aluminum molds encasing multiple layers (7) of woven material and a mandrel.

Abstract: A method for manufacturing a structural part including at least two wings extending in intersecting planes made of thermoplastic fiber-reinforced composite material including at least two plies of continuous fibers. The fibers extend from one wing to another. The method includes cutting the at least two plies in a fabric and/or a tape of fibers pre-impregnated with a thermoplastic resin; assembling the plies to create a preform; and compacting the preform to a final shape of the part by subjecting the preform to a defined cycle of temperature and pressure. A toolset can implement the method described above. Such a toolset includes a rigid punch and die such that closing the tool creates a sealed chamber in a shape of the part between the punch and the die.

Abstract: A composite structural element and a method for making same are provided. The element includes a polymer foam core and at least one fibrous layer adhered to the polymer foam core by epoxy. Nano-particles are suspended in the epoxy prior to curing; preferably they are mixed with the hardener before it is mixed with the resin. The polymer foam core is preferably an exothermic foam such as polyurethane, and heat generated by the exothermic foam cures the epoxy, thereby causing the fibrous layer to adhere to the foam core. The nano-particles may be made from at least one of carbon, a ceramic, tungsten, a carbide, titanium, zircon, aluminum, silver, or boron. When carbon nano-particles are used, the strength of the composite is greatly increased, and the curing time of the heat-curable epoxy is significantly reduced. Ceramic nano-particles can be used to increase penetration resistance and provide increased ballistic protection.

Abstract: A gas turbine engine blade for aircraft which has a 3-dimensional blade surface shape twisted around a center line at an angle of 45 degrees or more and 70 degrees or less, wherein the aforementioned blade is provided with multiple composite material prepregs which contain reinforced fiber and which are integrally molded after being laminated in the thickness direction, and the aforementioned reinforced fiber runs continuously without interruption within each layer of the aforementioned composite material prepregs.

Abstract: A method of assembling and shaping a laminate panel. An intermediate member is mounted on a lay-up table and a lay-up is assembling by laying a series of plies onto the intermediate member on the lay-up table. The intermediate member and the lay-up are then removed from the lay-up table and placed them on a shaped surface. The lay-up is then forced against the shaped surface, via the intermediate member, in a manner that modifies the shape of the lay-up to form a shaped laminate panel. Finally the shaped laminate panel is removed from the intermediate member. The lay-up table can thus support the flexible intermediate member during assembly, and can be relatively flat to enable the lay-up to assembled by an automated process.

Abstract: A non-compliant fiber-reinforced medical balloon comprises a first fiber layer and a second fiber layer embedded in a continuous matrix of thermally-weldable polymer material defining a barrel wall, cone walls and neck walls. The fibers of the first fiber layer run substantially parallel to one another and substantially parallel to the longitudinal axis. The fibers of the first fiber layer have a pattern of different lengths and are divisible into a first group and a second group based on length.

Abstract: A process for forming a composite structure includes the steps of: providing a preform having a plurality of layers; applying a tackifier to each of the layers of the preform; and infusing the preform with a resin. The tackifier may be catalyzed or uncatalyzed, thermoset or thermoplastic resin. The tackifier has a strain capability greater than the strain of the resin which infuses the preform.

Abstract: The disclosed embodiments concern a curved structural part composed of a composite material with reinforced, continuous fibers whose cross section includes at least two wings, with said fibers extending from one wing to the other, with said structural part having a variation in the width of its section parallel to the local radius of curvature. The structural element that results from assembling the parts in the disclosed embodiments therefore has local widening of the section at the connections between the parts constituting a structural element, such as an aircraft fuselage frame, and widening at the connection with the floor profiles, if such a profile is used to make an aircraft fuselage structure. The disclosed embodiments also concern a process for manufacturing such a part, as well as a device for advantageously implementing such a process.

Abstract: A novel reinforcement system for maximizing tensile strength and modulus of elasticity per ply for composite systems has one or more pockets with a first pocket edge, a second pocket edge, a pocket front surface, and a pocket rear surface. The pocket front surface and the pocket rear surface each have a pocket cross-stitch that perpendicularly traverses the pocket. The pocket traverses the fabric parallel and adjacent to the first fabric edge and the second fabric edge in a warp, or 0 degree, or x-axis direction. The pockets contain one or more fiber tows with a plurality of filaments in a stack.

Abstract: Systems and methods for the fabrication of prepregs possessing enhanced ability for the removal of gases from within prepregs and prepreg layups prior to and/or during at least a portion of consolidation and cure process to form composite structures are disclosed. In certain embodiments, perforations of selected configurations may be introduced into the prepregs prior to, during, and after layup. The perforations provide routes for gases trapped within and between the perforated prepregs and prepreg lay-ups to escape during consolidation and cure process, reducing the residual porosity within the resulting composite. For example, composites having residual porosities less than 10 vol. %, on the basis of the volume of the composite, may be achieved in this manner.

Abstract: A device changes the shape of a die used to compression mold a part. The device includes a sleeve placed between the die and a charge to be molded. The sleeve has an inner face generally conforming to a face of the die, and a outer face for molding a part.

Abstract: A method for fabricating a one-piece composite fuselage section that minimizes out-of-plane fiber distortion. This is accomplished by fabricating a mandrel having a coefficient of thermal expansion in the hoopwise direction that is sufficiently greater than that of the laid-up composite ply assembly. As a result of this differential in the coefficients of thermal expansion in the hoopwise direction, the laid-up composite ply assembly is stretched circumferentially as the mandrel expands radially during cure, thereby eliminating or reducing out-of-plane fiber distortion. At the same time, the mandrel and part being fabricated should have substantially the same coefficient of thermal expansion in the lengthwise direction. As the outer surface of the mandrel increases in circumference, the circumferentially oriented reinforcing fibers of the inner plies are stretched, while the circumferentially oriented reinforcing fibers of the outer plies do not reduce in circumference and thus do not form waves or wrinkles.

Abstract: Monolithic acoustically-treated composite structures and methods for fabricating the same are provided. A monolithic acoustically-treated composite structure comprises an internal frame assembly comprising a unitary composite frame structure and at least one acoustic panel assembly. The unitary composite frame structure defines a shape of the monolithic acoustically-treated composite structure to be fabricated. A composite overlay covers the internal frame assembly. The method for fabricating the monolithic acoustically-treated composite structure comprises forming the unitary composite frame structure, including the at least one acoustic panel in the unitary composite frame structure, and covering the internal frame assembly with the composite overlay.

Abstract: With a method for the manufacture of fiber-composite components, more particularly of fan blades for aircraft engines, dry fiber mats are superimposed in a lay-up mold, correctly positioned and fixed with locating pins and subsequently sewn in the mold. Metallic indicators are provided on at least one mat. The preformed entity of fiber mats is whipped at its edges with thermoplastic material and subsequently smoothed by application of heat. Remaining fiber residues are cut off. The blank thus available is infiltrated with synthetic resin in an infiltration mold or a sheathing remaining on the component. The fiber mats are checked for correct positioning by non-destructive inspection procedures. The fiber-composite component thus formed conforms to high quality requirements.

Abstract: The present invention relates to a universal frame for electric bikes and human powered bicycles, the frame body of the universal frame is consisted of a top tube, a down tube, a seat tube, two seat stays and two chain stays, wherein a holder is welded on the junction of the down tube, the seat tube and the chain stays, the holder is used to fasten on a bottom bracket shell with different specifications according to usage requirements. By the composition of the above elements, the present invention may be provided to assemble the main-shaft-chain wheel set of electric bikes or human powered bicycles, to thereby simplify the process, reduce the amount of inventories and achieve the convenience of universal interchangeability.

Abstract: A polymer matrix composites is formed from a preform layup from a plurality of fibers and is optionally tackified on its surface with a resin. The preform layup is placed in a vacuum bag and resin is flowed into the bag to infuse the layup to form a resin filled layup, then heated to increase the viscosity of the resin. The vacuum bag is vented to remove residual resin and/or entrapped gas, applying pressure to the preform layup in the bag to consolidate the layup to the target fiber volume, and the resin is cured.

Abstract: An apparatus and method for shaping an airfoil. A prepreg assembly is positioned relative to a part in a plurality of parts for a tool for the airfoil using a positioning section for a frame. The positioning section is configured to move relative to the tool and a base of the frame and move a number of parts in the plurality of parts for the tool relative to each other. A number of sections in the prepreg assembly are heated. A force is applied to the number of sections in the prepreg assembly that have been heated to conform to the tool to cause the number of sections in the prepreg assembly that have been heated to conform to the tool with a shape for a component of the airfoil.

Abstract: Provided is an anti-ballistic protective assembly including a plurality of layers of anti-ballistic material including at least two types of anti-ballistic materials, and an enclosure which is at least partially injection molded over the plurality of layers of anti-ballistic material and retains the plurality of layers of anti-ballistic material in a mutually compressed operative orientation.

Abstract: Processes for fabricating polymer composite materials that contain a polymer matrix, reinforcement fabrics, and particles of a filler material. The processes include spraying the particles of the filler material on at least two articles that each comprise at least one of the reinforcement fabrics to form particle-laden articles. The particle-laden articles are stacked to form a stacked structure, and a resin present within the stacked structure is then cured to form a laminate polymer composite material. The process can be employed in the fabrication of at least a portion of an aircraft engine nacelle, for example, the inlet lip of a fan nacelle.

Abstract: A method for manufacturing rigid panels made of a composite material requires a caul sheet having a smooth surface that is formed with a plurality of grooves. A first layer of the composite material is laid on the caul sheet, and is cut to create flaps that extend into the respective grooves. Strips of composite material are then placed along the edges of the groove to extend and overlap each other in the groove. Next, a unidirectional ply is placed along the length of the groove, and this combination is then covered with a second layer of the composite material. Together, the combination of the first and second layers, the strips and the unidirectional ply are co-cured to create a rigid panel with integral stiffening members.

Abstract: This relates to a method, a device and a curved molded member made of composite material. From at least one composite strip (24) formed of at least two tapes (3, 4, 5) made of unidirectional reinforcing fibers, pre-impregnated with resin and pre-compacted one with the other, the strip is applied longitudinally on a silicone flexible mandrel (13), by compaction under vacuum to confer the specific shape of the mandrel to it, the resulting strip (24) is deposited on a heated metal tool (31) having a curve that complements the shape of the mandrel and forming the core (32) of a pressure and temperature application mold (26), the flexible mandrel is removed then the mold is brought to pressure and temperature for polymerization, and the member is demolded after cooling.

Abstract: A tool is used to form a joint between a composite dome and a surrounding composite skirt. The tool includes a tool shell on which composite plies may be laid up to form the skirt and a spacer connected with the shell for filling a gap between the dome and the skirt.

Abstract: A method of manufacturing a rim for a bicycle wheel includes wrapping plys of fibers in a resin matrix around a mandrel; curing the plys to form the rim; and reducing a size of the mandrel to allow the mandrel to be removed from the rim.

Abstract: In an embodiment of the disclosure, there is provided a method to reduce porosity in a composite structure. The method adds an additive to a resin material to form an additive-resin mixture. The method combines the additive-resin mixture with reinforcement fibers to form a composite prepreg material, and in turn, a composite structure. The method heat cures the composite structure in a heating apparatus under a vacuum device at the resin cure temperature, heats the composite structure to an increased temperature above the additive phase transition temperature, and maintains the increased temperature for a time period sufficient. The method reduces the increased temperature back down to the resin cure temperature to allow the additive gas to undergo a phase transition to a condense phase, resulting in a substantially reduced vacuum pressure, resulting in a reduction in a porosity of the composite structure.