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56-464: The ABL facility is a manufacturer of advanced composite structures for the F-22 Raptor and other aerospace projects. ATK also operates 6 of 11 known advanced fiber placement machines . In addition the site produces about 80 military products, including: 30mm shells for Apache helicopters , training grenades , fuze-proximity sensors , mortars and warheads , and tank ammunition . Also on

112-633: A composite laminate is an assembly of layers of fibrous composite materials which can be joined to provide required engineering properties, including in-plane stiffness, bending stiffness , strength , and coefficient of thermal expansion . The individual layers consist of high- modulus , high-strength fibers in a polymeric , metallic , or ceramic matrix material. Typical fibers used include cellulose , graphite , glass , boron , and silicon carbide , and some matrix materials are epoxies , polyimides , aluminium , titanium , and alumina . Layers of different materials may be used, resulting in

168-421: A former ), continuous casting , filament winding , press moulding, transfer moulding , pultrusion moulding, and slip forming . There are also forming capabilities including CNC filament winding, vacuum infusion, wet lay-up, compression moulding , and thermoplastic moulding, to name a few. The practice of curing ovens and paint booths is also required for some projects. The composite parts finishing

224-635: A $ 177 million renovation and restoration program funded by the U.S. Naval Sea Systems Command (NAVSEA), which owns the Allegany Ballistics Laboratory. As for the ecological impact, it is believed the facility contributes greatly to the pollution of the adjacent North Branch Potomac River . While this is unsupported, the company does have numerous runoff sites. Also, the groundwater in the surrounding community has been verified to contain many contaminants, although actions have since been taken to reduce these contaminants, and are part of

280-413: A central core of end grain balsa wood , bonded to surface skins of light alloy or GRP. These generate low-weight, high rigidity materials. Particulate composites have particle as filler material dispersed in matrix, which may be nonmetal, such as glass, epoxy. Automobile tire is an example of particulate composite. Advanced diamond-like carbon (DLC) coated polymer composites have been reported where

336-551: A chemical reaction) into a rigid structure. Usually, the operation is done in an open or closed forming mould. However, the order and ways of introducing the constituents alters considerably. Composites fabrication is achieved by a wide variety of methods, including advanced fibre placement (automated fibre placement), fibreglass spray lay-up process , filament winding , lanxide process , tailored fibre placement , tufting , and z-pinning . The reinforcing and matrix materials are merged, compacted, and cured (processed) within

392-696: A co-curing or post-curing of the prepreg with many other media, such as foam or honeycomb. Generally, this is known as a sandwich structure . This is a more general layup for the production of cowlings, doors, radomes or non-structural parts. Open- and closed-cell-structured foams like polyvinyl chloride , polyurethane , polyethylene , or polystyrene foams, balsa wood , syntactic foams , and honeycombs are generally utilized core materials. Open- and closed-cell metal foam can also be utilized as core materials. Recently, 3D graphene structures ( also called graphene foam) have also been employed as core structures. A recent review by Khurram and Xu et al., have provided

448-594: A constant monitoring process. The following privately owned ventures are located on the ABL site: 39°33′40″N 78°50′5″W  /  39.56111°N 78.83472°W  / 39.56111; -78.83472 Composite materials A composite material (also called a composition material or shortened to composite , which is the common name) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create

504-1061: A high deformation setting and are often used in deployable systems where structural flexing is advantageous. Although high strain composites exhibit many similarities to shape-memory polymers, their performance is generally dependent on the fibre layout as opposed to the resin content of the matrix. Composites can also use metal fibres reinforcing other metals, as in metal matrix composites (MMC) or ceramic matrix composites (CMC), which includes bone ( hydroxyapatite reinforced with collagen fibres), cermet (ceramic and metal), and concrete . Ceramic matrix composites are built primarily for fracture toughness , not for strength. Another class of composite materials involve woven fabric composite consisting of longitudinal and transverse laced yarns. Woven fabric composites are flexible as they are in form of fabric. Organic matrix/ceramic aggregate composites include asphalt concrete , polymer concrete , mastic asphalt , mastic roller hybrid, dental composite , syntactic foam , and mother of pearl . Chobham armour

560-534: A hybrid laminate. The individual layers generally are orthotropic (that is, with principal properties in orthogonal directions) or transversely isotropic (with isotropic properties in the transverse plane) with the laminate then exhibiting anisotropic (with variable direction of principal properties), orthotropic, or quasi-isotropic properties. Quasi-isotropic laminates exhibit isotropic (that is, independent of direction) inplane response but are not restricted to isotropic out-of-plane (bending) response. Depending upon

616-709: A lightweight but thick core. The core material is normally low strength material, but its higher thickness provides the sandwich composite with high bending stiffness with overall low density . Wood is a naturally occurring composite comprising cellulose fibres in a lignin and hemicellulose matrix. Engineered wood includes a wide variety of different products such as wood fibre board, plywood , oriented strand board , wood plastic composite (recycled wood fibre in polyethylene matrix), Pykrete (sawdust in ice matrix), plastic-impregnated or laminated paper or textiles, Arborite , Formica (plastic) , and Micarta . Other engineered laminate composites, such as Mallite , use

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672-1417: A material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions . Composite materials with more than one distinct layer are called composite laminates . Typical engineered composite materials include: There are various reasons where new material can be favoured. Typical examples include materials which are less expensive, lighter, stronger or more durable when compared with common materials, as well as composite materials inspired from animals and natural sources with low carbon footprint. More recently researchers have also begun to actively include sensing, actuation, computation, and communication into composites, which are known as robotic materials . Composite materials are generally used for buildings , bridges , and structures such as boat hulls , swimming pool panels, racing car bodies, shower stalls, bathtubs , storage tanks , imitation granite , and cultured marble sinks and countertops. They are also being increasingly used in general automotive applications. The most advanced examples perform routinely on spacecraft and aircraft in demanding environments. The earliest composite materials were made from straw and mud combined to form bricks for building construction . Ancient brick-making

728-1064: A matrix of cement . Concrete is an inexpensive material, and will not compress or shatter even under quite a large compressive force. However, concrete cannot survive tensile loading (i.e., if stretched it will quickly break apart). Therefore, to give concrete the ability to resist being stretched, steel bars, which can resist high stretching (tensile) forces, are often added to concrete to form reinforced concrete . Fibre-reinforced polymers include carbon-fiber-reinforced polymers and glass-reinforced plastic . If classified by matrix then there are thermoplastic composites , short fibre thermoplastics , long fibre thermoplastics or long-fiber-reinforced thermoplastics . There are numerous thermoset composites, including paper composite panels . Many advanced thermoset polymer matrix systems usually incorporate aramid fibre and carbon fibre in an epoxy resin matrix. Shape-memory polymer composites are high-performance composites, formulated using fibre or fabric reinforcements and shape-memory polymer resin as

784-402: A mould to undergo a melding event. The part shape is fundamentally set after the melding event. However, under particular process conditions, it can deform. The melding event for a thermoset polymer matrix material is a curing reaction that is caused by the possibility of extra heat or chemical reactivity such as an organic peroxide. The melding event for a thermoplastic polymeric matrix material

840-802: A non-corrosive alternative to galvanized steel. In 2007, an all-composite military Humvee was introduced by TPI Composites Inc and Armor Holdings Inc, the first all-composite military vehicle . By using composites the vehicle is lighter, allowing higher payloads. In 2008, carbon fibre and DuPont Kevlar (five times stronger than steel) were combined with enhanced thermoset resins to make military transit cases by ECS Composites creating 30-percent lighter cases with high strength. Pipes and fittings for various purpose like transportation of potable water, fire-fighting, irrigation, seawater, desalinated water, chemical and industrial waste, and sewage are now manufactured in glass reinforced plastics. Composite materials used in tensile structures for facade application provides

896-3455: A rotation transformation (see transformation matrix ) it has the modified elasticity terms Q 11 ∗ = Q 11 cos 4 ⁡ θ + 2 ( Q 12 + 2 Q 66 ) sin 2 ⁡ θ cos 2 ⁡ θ + Q 22 sin 4 ⁡ θ Q 22 ∗ = Q 11 sin 4 ⁡ θ + 2 ( Q 12 + 2 Q 66 ) sin 2 ⁡ θ cos 2 ⁡ θ + Q 22 cos 4 ⁡ θ Q 12 ∗ = ( Q 11 + Q 22 − 4 Q 66 ) sin 2 ⁡ θ cos 2 ⁡ θ + Q 12 ( sin 4 ⁡ θ + cos 4 ⁡ θ ) Q 66 ∗ = ( Q 11 + Q 22 − 2 Q 12 − 2 Q 66 ) sin 2 ⁡ θ cos 2 ⁡ θ + Q 66 ( sin 4 ⁡ θ + cos 4 ⁡ θ ) Q 16 ∗ = ( Q 11 − Q 12 − 2 Q 66 ) cos 3 ⁡ θ sin ⁡ θ − ( Q 22 − Q 12 − 2 Q 66 ) cos ⁡ θ sin 3 ⁡ θ Q 26 ∗ = ( Q 11 − Q 12 − 2 Q 66 ) cos ⁡ θ sin 3 ⁡ θ − ( Q 22 − Q 12 − 2 Q 66 ) cos 3 ⁡ θ sin ⁡ θ {\displaystyle {\begin{aligned}Q_{11}^{*}&=Q_{11}\cos ^{4}\theta +2(Q_{12}+2Q_{66})\sin ^{2}\theta \cos ^{2}\theta +Q_{22}\sin ^{4}\theta \\Q_{22}^{*}&=Q_{11}\sin ^{4}\theta +2(Q_{12}+2Q_{66})\sin ^{2}\theta \cos ^{2}\theta +Q_{22}\cos ^{4}\theta \\Q_{12}^{*}&=(Q_{11}+Q_{22}-4Q_{66})\sin ^{2}\theta \cos ^{2}\theta +Q_{12}(\sin ^{4}\theta +\cos ^{4}\theta )\\Q_{66}^{*}&=(Q_{11}+Q_{22}-2Q_{12}-2Q_{66})\sin ^{2}\theta \cos ^{2}\theta +Q_{66}(\sin ^{4}\theta +\cos ^{4}\theta )\\Q_{16}^{*}&=(Q_{11}-Q_{12}-2Q_{66})\cos ^{3}\theta \sin \theta -(Q_{22}-Q_{12}-2Q_{66})\cos \theta \sin ^{3}\theta \\Q_{26}^{*}&=(Q_{11}-Q_{12}-2Q_{66})\cos \theta \sin ^{3}\theta -(Q_{22}-Q_{12}-2Q_{66})\cos ^{3}\theta \sin \theta \end{aligned}}} Hence [ σ ] ∗ = Q ∗ [ ε ] ∗ {\displaystyle [\sigma ]^{*}=\mathbf {Q} ^{*}[\varepsilon ]^{*}} An important assumption in

952-513: A significant role in continuity of government operations. ABL was established in 1944 on the site of a former ammunitions plant on land owned by the Army. After World War II, the plant was transferred to the Office of Scientific Research and Development and was involved in building propulsion devices and engines for the solid-rocket industry. Later in the decade, ownership of ABL was transferred to

1008-408: A strong influence on both the stiffness and strength of the laminate as a whole. Rotating an anisotropic material results in a variation of its elasticity tensor . If in its local co-ordinates a ply is assumed to behave according to the stress-strain law [ σ ] = Q [ ε ] {\displaystyle [\sigma ]=\mathbf {Q} [\varepsilon ]} then under

1064-440: A three-dimensional stress field is replaced by six stress resultants; three membrane forces (forces per unit length) and bending moments per unit length. It is assumed that if these three quantities are known at any location (x,y) then the stresses may be computed from them. Once part of a laminate the transformed elasticity is treated as a piecewise function of the thickness direction, hence the integration operation may be treated as

1120-413: Is a solidification from the melted state. The melding event for a metal matrix material such as titanium foil is a fusing at high pressure and a temperature near the melting point. It is suitable for many moulding methods to refer to one mould piece as a "lower" mould and another mould piece as an "upper" mould. Lower and upper does not refer to the mould's configuration in space, but the different faces of

1176-578: Is a special type of composite armour used in military applications. Additionally, thermoplastic composite materials can be formulated with specific metal powders resulting in materials with a density range from 2 g/cm to 11 g/cm (same density as lead). The most common name for this type of material is "high gravity compound" (HGC), although "lead replacement" is also used. These materials can be used in place of traditional materials such as aluminium, stainless steel, brass, bronze, copper, lead, and even tungsten in weighting, balancing (for example, modifying

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1232-424: Is also crucial in the final design. Many of these finishes will involve rain-erosion coatings or polyurethane coatings. The mould and mould inserts are referred to as "tooling". The mould/tooling can be built from different materials. Tooling materials include aluminium , carbon fibre , invar , nickel , reinforced silicone rubber and steel. The tooling material selection is normally based on, but not limited to,

1288-469: Is also used in payload adapters, inter-stage structures and heat shields of launch vehicles . Furthermore, disk brake systems of airplanes and racing cars are using carbon/carbon material, and the composite material with carbon fibres and silicon carbide matrix has been introduced in luxury vehicles and sports cars . In 2006, a fibre-reinforced composite pool panel was introduced for in-ground swimming pools, residential as well as commercial, as

1344-441: Is another main factor. To support high capital investments for rapid and automated manufacturing technology, vast quantities can be used. Cheaper capital investments but higher labour and tooling expenses at a correspondingly slower rate assists the small production quantities. Many commercially produced composites use a polymer matrix material often called a resin solution. There are many different polymers available depending upon

1400-410: Is needed at least. The reinforcement receives support from the matrix as the matrix surrounds the reinforcement and maintains its relative positions. The properties of the matrix are improved as the reinforcements impart their exceptional physical and mechanical properties. The mechanical properties become unavailable from the individual constituent materials by synergism. At the same time, the designer of

1456-415: Is no delamination at the fibre-matrix interface). This isostrain condition provides the upper bound for composite strength, and is determined by the rule of mixtures : where E C is the effective composite Young's modulus , and V i and E i are the volume fraction and Young's moduli, respectively, of the composite phases. For example, a composite material made up of α and β phases as shown in

1512-446: Is that they are able to have shape memory behaviour without needing any shape-memory polymers or shape-memory alloys e.g. balsa plies interleaved with hot glue, aluminium plies interleaved with acrylic polymers or PVC and carbon-fiber-reinforced polymer laminates interleaved with polystyrene . A sandwich-structured composite is a special class of composite material that is fabricated by attaching two thin but stiff skins to

1568-452: The coefficient of thermal expansion , expected number of cycles, end item tolerance, desired or expected surface condition, cure method, glass transition temperature of the material being moulded, moulding method, matrix, cost, and other various considerations. Usually, the composite's physical properties are not isotropic (independent of the direction of applied force) in nature. But they are typically anisotropic (different depending on

1624-702: The Navy office of Naval Sea Systems Command . Since 1946 it was operated by the Hercules Powder Company . In 1956 when it was producing Altair rocket stages for Vanguard rockets , ABL was, "A subsidiary of the Navy operated by the Hercules Powder Company." The Navy now contracts out operation of the facility to ATK (Alliant Techsystems) , a $ 3.4 billion corporation based in Edina, Minnesota . In 1998, ATK's Conventional Munitions Group

1680-667: The advantage of being translucent. The woven base cloth combined with the appropriate coating allows better light transmission. This provides a very comfortable level of illumination compared to the full brightness of outside. The wings of wind turbines, in growing sizes in the order of 50 m length are fabricated in composites since several years. Two-lower-leg-amputees run on carbon-composite spring-like artificial feet as quick as non-amputee athletes. High-pressure gas cylinders typically about 7–9 litre volume x 300 bar pressure for firemen are nowadays constructed from carbon composite. Type-4-cylinders include metal only as boss that carries

1736-428: The case of spider silk, the properties of the material can even be dependent on the size of the crystals, independent of the volume fraction. Ironically, single component polymeric materials are some of the most easily tunable composite materials known. Normally, the fabrication of composite includes wetting, mixing or saturating the reinforcement with the matrix. The matrix is then induced to bind together (with heat or

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1792-644: The centre of gravity of a tennis racquet ), vibration damping, and radiation shielding applications. High density composites are an economically viable option when certain materials are deemed hazardous and are banned (such as lead) or when secondary operations costs (such as machining, finishing, or coating) are a factor. There have been several studies indicating that interleaving stiff and brittle epoxy-based carbon-fiber-reinforced polymer laminates with flexible thermoplastic laminates can help to make highly toughened composites that show improved impact resistance. Another interesting aspect of such interleaved composites

1848-684: The co-ordinate system at the laminate level. Individual plies have local co-ordinate axes which are aligned with the materials characteristic directions; such as the principal directions of its elasticity tensor. Uni-directional ply's for example always have their first axis aligned with the direction of the reinforcement. A laminate is a stack of individual plies having a set of ply orientations [ θ 1 , θ 2 , … θ N ] {\displaystyle {\begin{bmatrix}\theta _{1},&\theta _{2},&\dots &\theta _{N}\end{bmatrix}}} which have

1904-941: The coating increases the surface hydrophobicity, hardness and wear resistance. Ferromagnetic composites, including those with a polymer matrix consisting, for example, of nanocrystalline filler of Fe-based powders and polymers matrix. Amorphous and nanocrystalline powders obtained, for example, from metallic glasses can be used. Their use makes it possible to obtain ferromagnetic nanocomposites with controlled magnetic properties. Fibre-reinforced composite materials have gained popularity (despite their generally high cost) in high-performance products that need to be lightweight, yet strong enough to take harsh loading conditions such as aerospace components ( tails , wings , fuselages , propellers ), boat and scull hulls, bicycle frames, and racing car bodies. Other uses include fishing rods , storage tanks , swimming pool panels, and baseball bats . The Boeing 787 and Airbus A350 structures including

1960-798: The composite is σ C = E α V α ϵ + E β V β ϵ = ( E α V α + E β V β ) ϵ {\displaystyle \sigma _{C}=E_{\alpha }V_{\alpha }\epsilon +E_{\beta }V_{\beta }\epsilon =(E_{\alpha }V_{\alpha }+E_{\beta }V_{\beta })\epsilon } Then it can be shown that E C = ( E α V α + E β V β ) {\displaystyle E_{C}=(E_{\alpha }V_{\alpha }+E_{\beta }V_{\beta })} Composite laminate In materials science ,

2016-1066: The direction normal to the laminates surface. The broad majority of ply or lamina materials obey Hooke's law and hence all of their stresses and strains may be related by a system of linear equations . Laminates are assumed to deform by developing three strains of the mid-plane/surface and three changes in curvature ε 0 = [ ε x 0 ε y 0 τ x y 0 ] T {\displaystyle \varepsilon ^{0}={\begin{bmatrix}\varepsilon _{x}^{0}&\varepsilon _{y}^{0}&\tau _{xy}^{0}\end{bmatrix}}^{T}} and κ = [ κ x κ y κ x y ] T {\displaystyle \kappa ={\begin{bmatrix}\kappa _{x}&\kappa _{y}&\kappa _{xy}\end{bmatrix}}^{T}} where x {\displaystyle x} and y {\displaystyle y} define

2072-410: The direction of the applied force or load). For instance, the composite panel's stiffness will usually depend upon the orientation of the applied forces and/or moments. The composite's strength is bounded by two loading conditions, as shown in the plot to the right. If both the fibres and matrix are aligned parallel to the loading direction, the deformation of both phases will be the same (assuming there

2128-470: The figure to the right under isostrain, the Young's modulus would be as follows: E C = V α E α + V β E β {\displaystyle E_{C}=V_{\alpha }E_{\alpha }+V_{\beta }E_{\beta }} where V α and V β are the respective volume fractions of each phase. This can be derived by considering that in

2184-514: The final product, or the fibre content is increased. As a rule of thumb, lay up results in a product containing 60% resin and 40% fibre, whereas vacuum infusion gives a final product with 40% resin and 60% fibre content. The strength of the product is greatly dependent on this ratio. Martin Hubbe and Lucian A Lucia consider wood to be a natural composite of cellulose fibres in a matrix of lignin . Several layup designs of composite also involve

2240-414: The individual phases are given by Hooke's Law, σ β = E β ϵ {\displaystyle \sigma _{\beta }=E_{\beta }\epsilon } σ α = E α ϵ {\displaystyle \sigma _{\alpha }=E_{\alpha }\epsilon } Combining these equations gives that the overall stress in

2296-651: The isostrain case, ϵ C = ϵ α = ϵ β = ϵ {\displaystyle \epsilon _{C}=\epsilon _{\alpha }=\epsilon _{\beta }=\epsilon } Assuming that the composite has a uniform cross section, the stress on the composite is a weighted average between the two phases, σ C = σ α V α + σ β V β {\displaystyle \sigma _{C}=\sigma _{\alpha }V_{\alpha }+\sigma _{\beta }V_{\beta }} The stresses in

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2352-764: The less stiff, amorphous phase. Polymeric materials can range from 0% to 100% crystallinity aka volume fraction depending on molecular structure and thermal history. Different processing techniques can be employed to vary the percent crystallinity in these materials and thus the mechanical properties of these materials as described in the physical properties section. This effect is seen in a variety of places from industrial plastics like polyethylene shopping bags to spiders which can produce silks with different mechanical properties. In many cases these materials act like particle composites with randomly dispersed crystals known as spherulites. However they can also be engineered to be anisotropic and act more like fiber reinforced composites. In

2408-406: The matrix nature, such as solidification from the melted state for a thermoplastic polymer matrix composite or chemical polymerization for a thermoset polymer matrix . According to the requirements of end-item design, various methods of moulding can be used. The natures of the chosen matrix and reinforcement are the key factors influencing the methodology. The gross quantity of material to be made

2464-625: The matrix. Since a shape-memory polymer resin is used as the matrix, these composites have the ability to be easily manipulated into various configurations when they are heated above their activation temperatures and will exhibit high strength and stiffness at lower temperatures. They can also be reheated and reshaped repeatedly without losing their material properties. These composites are ideal for applications such as lightweight, rigid, deployable structures; rapid manufacturing; and dynamic reinforcement. High strain composites are another type of high-performance composites that are designed to perform in

2520-420: The moulded panel. There is always a lower mould, and sometimes an upper mould in this convention. Part construction commences by applying materials to the lower mould. Lower mould and upper mould are more generalized descriptors than more common and specific terms such as male side, female side, a-side, b-side, tool side, bowl, hat, mandrel, etc. Continuous manufacturing utilizes a different nomenclature. Usually,

2576-451: The moulded product is referred to as a panel. It can be referred to as casting for certain geometries and material combinations. It can be referred to as a profile for certain continuous processes. Some of the processes are autoclave moulding , vacuum bag moulding , pressure bag moulding , resin transfer moulding , and light resin transfer moulding . Other types of fabrication include casting , centrifugal casting, braiding (onto

2632-477: The product or structure receives options to choose an optimum combination from the variety of matrix and strengthening materials. To shape the engineered composites, it must be formed. The reinforcement is placed onto the mould surface or into the mould cavity. Before or after this, the matrix can be introduced to the reinforcement. The matrix undergoes a melding event which sets the part shape necessarily. This melding event can happen in several ways, depending upon

2688-505: The site is the Robert C. Byrd Hilltop Office Complex and the Robert C. Byrd Institute for Advanced Flexible Manufacturing. At the Robert C. Byrd Complex on the hill companies have rented space to do secure research, among them IBM (which recently acquired National Interest Security Company ) who is digitizing data on hurricane cleanup, avian influenza , and weather records. It also plays

2744-418: The stacking sequence of the individual layers, the laminate may exhibit coupling between inplane and out-of-plane response. An example of bending-stretching coupling is the presence of curvature developing as a result of in-plane loading. Composite laminates may be regarded as a type of plate or thin-shell structure , and as such their stiffness properties may be found by integration of in-plane stress in

2800-404: The starting raw ingredients. There are several broad categories, each with numerous variations. The most common are known as polyester , vinyl ester , epoxy , phenolic , polyimide , polyamide , polypropylene , PEEK , and others. The reinforcement materials are often fibres but also commonly ground minerals. The various methods described below have been developed to reduce the resin content of

2856-447: The summary of the state-of-the-art techniques for fabrication of the 3D structure of graphene, and the examples of the use of these foam like structures as a core for their respective polymer composites. Although the two phases are chemically equivalent, semi-crystalline polymers can be described both quantitatively and qualitatively as composite materials. The crystalline portion has a higher elastic modulus and provides reinforcement for

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2912-417: The theory of classical laminate analysis is that the strains resulting from curvature vary linearly in the thickness direction, and that the total in-plane strains are a sum of those derived from membrane loads and bending loads. Hence ε = ε 0 + κ ⋅ z {\displaystyle \varepsilon =\varepsilon ^{0}+\kappa \cdot z} Furthermore,

2968-477: The thread to screw in the valve. On 5 September 2019, HMD Global unveiled the Nokia 6.2 and Nokia 7.2 which are claimed to be using polymer composite for the frames. Composite materials are created from individual materials. These individual materials are known as constituent materials, and there are two main categories of it. One is the matrix ( binder ) and the other reinforcement . A portion of each kind

3024-414: The wings and fuselage are composed largely of composites. Composite materials are also becoming more common in the realm of orthopedic surgery , and it is the most common hockey stick material. Carbon composite is a key material in today's launch vehicles and heat shields for the re-entry phase of spacecraft . It is widely used in solar panel substrates, antenna reflectors and yokes of spacecraft. It

3080-442: Was documented by Egyptian tomb paintings . Wattle and daub is one of the oldest composite materials, at over 6000 years old. Concrete is also a composite material, and is used more than any other synthetic material in the world. As of 2009 , about 7.5 billion cubic metres of concrete are made each year Concrete is the most common artificial composite material of all and typically consists of loose stones (aggregate) held with

3136-484: Was selected by Lockheed Martin Aeronautical Systems to produce the fiber-placed composite pivot shaft assembly for the F-22 Raptor air-dominance fighter. Work on the production program was performed at Alliant's automated fiber placement production facility at the Allegany Ballistics Laboratory before the production of F-22 aircraft ended in 2012. The fiber placement facility was constructed as part of

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