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COMPOSITES BY ALANKAR G. MHATRE FINAL YEAR B.TECH CONTENTS • Introduction • What are composites? • Composition of composites • Types of composites • Manufacturing and forming methods • Applications • Composites Today's Material of Choice • Properties of composites • Key manufacturers of composite products • References INTRODUCTION TO COMPOSITES You might be know we all are surrounded by composites in day today life. Everybody comes across composites in his daily life.You might be playing tennis or badminton with a "graphite racket", You might have a "carbon bike" ,your bike breaks are made of composite, several parts of your car body are also made of composites. Def :-A composite is a material made up of two or more different materials that are combined in a way that allows the materials to stay distinct and identifiable. The purpose of composites is to allow the new material to have strengths from both materials. • Composites can be easily found in nature. Wood is an example of a composite . Another natural composite is rock and sand, materials used in concrete. Properties of composites like stiffness, thermal expansion etc. can be varied continuously over a broad range of values using appropriate fiber , resin and fabrication mechanism. The technical textile material in the composites is the fiber glass, aramid and carbon fiber. • Fibre glass dominates the composites industry as a preferred reinforcement fibre, with a share of around 85%-90%. Other reinforcement fibers like carbon fibre and aramid fibre are sparingly used in India. WHAT ARE COMPOSITES? Composites are created by combining two or more materials to produce a new material that retains important properties from the original elements . Reinforcing fibers give composites the attributes of high strength and stiffness. In textile composites fibers are surrounded by a choice of polymers that act as a support system. Composites are produced by reinforcing a resin matrix (thermoplastic/thermoset) with fibres like glass fibre, aramid, carbon fibre and/or natural fibres. A common example of a composite is concrete. It consists of a binder as a cement and a reinforcement as a gravel. COMPOSITION OF COMPOSITES The individual materials that make up composites are called constituents. Most composites have two constituents, a matrix and reinforcement. Composite materials are usually classified by the type of reinforcement they use. This reinforcement is embedded into a matrix that hold it together. The reinforcement is used to strengthen the composite. Composite properties are best in the direction of the fibers. Perpendicular, or transverse, to the fibers, the matrix properties dominate because load must be transferred by the matrix every fiber diameter. Reinforcement The reinforcement is usually much stronger and stiffer than the matrix, and that gives the composite its good properties. The matrix hold the reinforcements in an orderly pattern, the matrix also helps to transfer load among the reinforcements. Reinforcements basically come in three forms: particulate, discontinuous fiber, and continuous fiber. PARTICLE AS A REINFORCEMENT:-A particle has roughly equal dimensions in all directions, though it doesn't have to be spherical. Gravel, micro balloons, and resin powder are examples of particulate reinforcements. CONTINUES FIBER AS A REINFORCEMENT:-Reinforcements become fibers when one dimension becomes long compared to others. DISCONTINUES FIBERS AS A REINFORCEMENT: -:Discontinuous reinforcements (chopped fibers, milled fibers, or whiskers) vary in length from a few millimeters to a few centimeters. Most fibers are only a few microns in diameter, so it doesn't take much length to make the transition from particle to fiber. MATRIX Matrix materials are usually some type of plastic, and these composites are often called reinforced plastics. There are other types of matrices, such as metal or ceramic, but plastics are the most . The two most common plastic matrices are epoxy resins and polyester resins. TYPES OF COMPOSITES Metal matrix composites (MMC) Ceramic matrix composites (CMC) Polymer matrix composites (PMC) [...]... frame very stiff and lightweight BMW M6 with carbon fibre roof In automotive applications, composites are all around us Just as in sports applications, weight reduction is pushing the designers to use more and more composites The examples are numerous Composites Today's Material of Choice • It gives lower manufacturing costs, composite material continues to penetrate new markets and applications... burners, flame holders, and hot gas ducts, where the use of oxide CMCs has found its way Disks breaks and brake system components, which experience extreme thermal shock Applications of FRP or PMC • • Fibre-reinforced plastics are best suited for any design program that demands weight savings, precision engineering, finite tolerances, and the simplification of parts in both production and operation A moulded... filaments and therefore is called chemical vapor infiltration (CVI) One example is the manufacture of C/C composites: a C-fiber perform is exposed to a mixture of argon and a hydrocarbon gas (methane, propane, etc.) at a pressure of around or below 100 kPa and a temperature above 1000 °C 2)-Matrix forming via pyrolysis of C- and Si-containing polymers Hydrocarbon polymers shrink during paralysis, and. .. reduced after every cycle APPLICATION OF COMPOSITES • Applications of Métal matrix composites (MMC)– 1 Carbide drills are often made from a tough cobalt matrix with hard tungsten carbide particles inside Some tank armors may be made from metal matrix composites, probably steel reinforced with boron nitride Boron nitride is a good reinforcement for steel because it is very stiff and it does not dissolve... conductivity A typical composites material construction for helicopter blade Metal matrix composites Applications Of ceramic matrix composites • • • • Heat shield systems for space vehicles, which are needed during the re-entry phase, where high temperatures, thermal shock conditions and heavy vibration loads take place Components for high-temperature gas turbines such as combustion chambers, and turbine blades... combination of type of fiber / type of matrix For example, C/C stands for carbon-fiber-reinforced carbon (carbon/carbon), or C/ SiC for carbon-fiber-reinforced silicon carbide Ceramic composites REINFORCEMENT- SiC (Silicon carbide) MATRIX-Cu Metal Polymer Matrix composites Polymer matrix composites are the imp and third subgroup of composites It is also referred as fibre-reinforced plastics(FRP)... both production and operation A moulded polymer artefact is cheaper, faster, and easier to manufacture than cast aluminum or steel artefact, and maintains similar and sometimes better tolerances and material strengths Overall reduction in production and operational costs, economy of parts results in lower production costs and the weight savings create fuel savings that lower the operational costs of... arrangement of fibres, a braid, a knit Manufacturing and forming methods of MMC MMC manufacturing can be broken into three types: solid, liquid, and vapor Solid state methods: 1)-Powder blending and consolidation (powder metallurgy):Powdered metal and discontinuous reinforcement are mixed and then bonded through a process of compaction, degassing, and thermo-mechanical treatment (possibly via hot isostatic... stiffness and impact properties Higher fatigue endurance limit (up to 60% of the ultimate tensile strength) 30-45% lighter than aluminium structures designed for the same functional requirements Lower embedded energy Composites are less noisy while in operation and provide lower vibration transmission Composites are more versatile and can be tailored to meet performance needs and complex... category are alumina and silicon carbide Ceramic matrix composites Ceramic matrix composites (CMCs) are a subgroup of composite materials as well as a subgroup of technical ceramics They consist of ceramic fibers embedded in a ceramic matrix, thus forming a ceramic fiber reinforced ceramic (CFRC) material The matrix and fibers can consist of any ceramic material, whereby carbon and carbon fibers . and polyester resins. TYPES OF COMPOSITES Metal matrix composites (MMC) Ceramic matrix composites (CMC) Polymer matrix composites (PMC) Metal matrix composites (MMC) • Metal matrix composites. COMPOSITES BY ALANKAR G. MHATRE FINAL YEAR B.TECH CONTENTS • Introduction • What are composites? • Composition of composites • Types of composites • Manufacturing and forming methods • Applications. . Reinforcing fibers give composites the attributes of high strength and stiffness. In textile composites fibers are surrounded by a choice of polymers that act as a support system. Composites are