Composites are similar to essays; they are both an arrangement of parts coming together. Composites, however, have two essential phases: matrix and dispersed phase. The matrix’s responsibility is to be covering the materials being used to form a new type of supply. Composites are also known as two or more type of materials being combine to create a new material that could be used in different real world applications. Commonly, composites are formed because it could be reusable, cheaper and sometimes a stronger material. Three of the most common use materials to form composites are metals, polymers and ceramics [1]. The combination of these materials provides suppliers more opportunities to create composites that will be used often in the market. But to construct composites, suppliers must understand how composites work. They are divided into three different composites: particle-reinforced composites, fiber-reinforced composites, and structural composites [1].
Particle-reinforced composites move into two divisions which are large particles and dispersion-strength. Large particles go under the condition which the contact between particle-matrix cannot be treated on the atomic or molecule level, whereas a different way such continuum mechanics is used. The filler used for particle-reinforced composites usually alternate the properties of the material or could substitute some of the polymer volume with cheaper material. In this case, the smaller and the more evenly spread throughout the matrix the particles are, there is an increasing of effective reinforcement. A good example of a large-particle composite is concrete [1]. In the other hand of particle-reinforcement composites, the dispersed particles are considered small which allows...
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... of a very stiff and strong material such as fiber-reinforcement plastics, steel, titanium or plywood. All this elements that help understand how composites are constructed can be in real world applications.
An example of one of the most common world applications where composites play a big role is bridges. A good number of bridges are held my concrete columns. The composites to fulfill this type of application are being alternated to help increase its ductility. The number of plate boding to involve thin composite laminates helps strengthen the concrete and many of the steel members for bridges. A bridge that was one of the first opened to car activity with the usage of composites was in Kansa City in 1996. This bridge was composited by honeycomb cells which were structural sandwiched. This allowed composites to be used among other bridges across the nation [2].
Television has affected every aspect of life in society, radically changing the way individuals live and interact with the world. However, change is not always for the better, especially the influence of television on political campaigns towards presidency. Since the 1960s, presidential elections in the United States were greatly impacted by television, yet the impact has not been positive. Television allowed the public to have more access to information and gained reassurance to which candidate they chose to vote for. However, the media failed to recognize the importance of elections. Candidates became image based rather than issue based using a “celebrity system” to concern the public with subjects regarding debates (Hart and Trice). Due to “hyperfamiliarity” television turned numerous people away from being interested in debates between candidates (Hart and Trice). Although television had the ability to reach a greater number of people than it did before the Nixon/Kennedy debate, it shortened the attention span of the public, which made the overall process of elections unfair, due to the emphasis on image rather than issue.
Dec. 2013. 14 Wikipedia contributors. The "Ceramic matrix composite" Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 14 Nov. 2013. Web.
Standing on the edge of a platform ninety feet up in the air, I’m scared. But once I push off, I’m soaring on a zip line, flying through the air, exhilarated. Taking that step off of the platform was one of the hardest things I’ve done, but once I took the step off the platform, I wouldn’t take it back for the world. It’s just like college; I’m set on going, but our society today weighs the risks and the rewards- whether or not college is worth attending. On the other hand, while there are legitimate drawbacks to obtaining a college degree, the fact remains that a college education sees most people to go further in life than those without.
The longer carbon fiber composites are in demand and products are being built, the cheaper the material will become and an increase in strength, a decrease in weight, and an overall better and more efficient product will be produced. Carbon fiber composites are truly a unique and revolutionary
Many materials when they are in fibrous form exhibit very good strength properties but to achieve these properties the fiber should be bonded by a suitable matrix. The matrix isolates the fibers from one another in order to prevent abrasion and formation of new surface flaws and acts as a bridge to hold the fibers in place. A good matrix should possess ability to deform easily under applied load, transfer the load on to the fibers and evenly distribute stress concentration.
When building sandwich composite structures, the materials are shapeable in almost any kind of form until the last stage of production in which they get their final shape. This allows for non-linear and smooth designs, which can be done not only for aesthetic reasons but also for aerodynamic reasons. Other advantages of using sandwich composites are that they provide thermal insulation, sound insulation, good corrosion resistance, resistance to moisture, and final structures can be repaired easily.
1996Cast metal matrix composites are first used in production model automobile in the brake rotors for the Lotus Elise.
Who would have ever imagined that one day composites would be widely used? Who even know what composites are? Looking at past memories, metals were the main materials used to construct structures and many other things. This is because they are strong and can provide good resistivity. But in the other hands, metals though have really good properties, also come along with some bad ones. Most metals used are of high densities and heavy. So their application in some places is limited and also they are costly. Due to these problems new materials had to be looked for, materials that can show strong vitality, high tensile strength as metals, high volume, good stiffness, materials which can show resistance to corrosion and fatigue, materials which have excellent damping properties and finally an excellent overall curing forming process.
Concrete is a composite material composed of water, coarse granular material embedded in hard matrix of material (the cement or binder) that fills the space among the particles and glues them together. Concrete is known by Romans as old as 12 million years. It was a revolutionary material laid in the shape of arches, vaults and domes. Concrete is widely used for making architectural structures, foundations, brick/block walls, pavements, bridges/overpasses, highways, runways, parking structures, dams, pools/reservoirs, pipes, footings for gates, fences and poles and even boats. From roman to now Concrete has taken many designs. Present researchers have experimented with addition of materials to create improved properties such as strength or electrical conductivity.
The environmental friendly and biodegradable nature of natural fiber has enabled it to be used in composite materials as filler. Over the past few decades natural fibers have been able to replace the synthetic fibers in composites materials due to many superior properties like low cost, high stiffness to weight ratio, high availability, low density and biodegradability.
Since the Wright Flyer first took off from Kitty Hawk, North Carolina, in 1903, aircraft designers have been searching for ever better materials to build aircraft with. Over the years, we have seen construction materials progress from simple wood frames covered with fabric to advanced structures built entirely out of metal. As aircraft designs became more advanced, the need arose for materials which offered both higher strength and lighter weight. Since the beginning of World War II, aircraft construction consisted mainly of structures built from aluminum. Beginning in the 1960’s, NASA and the United States military began experimenting with the use of composite materials in aircraft. This revolutionary material seemed to be the answer the aviation world was looking for. It promised both gains in strength and weight reduction. However, with more and more composites being added to aircraft over the years, problems arose which ultimately may negate the overall benefits of the composites.
The word ‘composite’ does not fully explain the wide range and varied compositions of materials that are categorized under it. This paper deals with some of the commonly used composites. Common materials such as metallic, ceramic and polymers consists of substances that can be classified as composites. The steel family, which is considered as the biggest group of material that is used in construction and complex engineering, is composed of composites that are made out of soft metallic matrix and hard ceramic components. [11] Such metallic composites could be shaped as a plate, needle, sphere or be polygonal. Polymeric composites are also found in a similar matrix model where one polymer forms the skeleton and another hard or soft polymer fills the matrix. A good example of this would be wood. Concrete is also a popular matrix composite where the Portland cement provides the matrix phase and the inner filling is made up of sands of different size. Scientists are now able to adjust the composition of these composites to suit the various needs. This adjustment is done by tweaking the microstructure of the materials by changing the state, shape, amount and distribution of the filling, which is also called as the reinforcing phase. Instead of restricting this tweaking process within a certain material class, the idea is being implementing in cross-material classes as well. Ceramics powder can be added to plastics to make hard and fireproof polymers. Ceramic powder when mixed with metals, gives cermets, which are used in tips of metal cutting tools. Another branch of the same idea is the blending of metal filaments, ceramic and polymer into one large bulk to form metal-matrix composites (MMCs), reinforced plastics (RP) and ceramic-matrix composites (CMCs). Such a radical idea of mixing all the three classes of materials has resulted in composites such as carbon fibre reinforced plastic (CFRP), glass reinforced plastic (GRP) and silicon-carbon-fibre-reinforced aluminium. Figure1 shows Comparison between conventional monolithic material and composite material. [17, 18,10and1
A composite material is a non-uniform solid consisting of two or more different materials that are mechanically bonded together. Each of the various components retains its identity in the composite and maintains its characteristic structure and properties. Generally, the structure of a composite consists of two phases, matrix and reinforcement. The matrix is a continuous phase and the reinforcement is a discontinuous one. The duty of reinforcements is attaining strength of the composite and the matrix has the responsibility of bonding of the reinforcements.
Materials are often chosen to fulfill certain structural or load requirements. To make the optimum use of the properties needed and the material used, two or more materials can be combined to give desired properties. Earlier metals were combined to yield alloys which had suitable properties. But as requirement became more and more demanding, it was found that necessary properties could be obtained by combining chemically different materials to create a new material with desired properties. The objective of mechanical testing of composite is to determine the mechanical parameters such as strength and stiffness which is used to design and to find suitable application for the composite. These tests are performed according to ASTM standard procedure in a controlled environment. Mainly mechanical test include three basic tests that are:
Composite is the combination of matrix and reinforcement material, which will have more strength when compared to the matrix and reinforcement material. The reinforcement material may present in the form of particulates, flakes and fibers. The strength and stiffness of the composite material is depends on the shape, size and way of orientation of reinforcements arranged in the matrix material. The different types of composite materials are metal matrix composites (MMC), ceramic matrix composites (CMC) and polymer matrix composites (PMC).