A composite material is defined as a mixture of 2 or more material that results in improved properties than those of the individual components used. In comparison to metallic alloy, each material retains its separate electrical, physical, and mechanical properties. The 2 materials are reinforcement and a matrix is developed. The main advantages of composite materials are their high strengths and stiffness, combined with less density, when compared with bulk material, resulting in a weight reduction in the finished part. In maximum cases, the reinforcement is harder, stronger, and stiff than matrix. The reinforcement is usually a fibre. Particulate composites have dimensions that are uniformly equal in all directions. They are spherical, platelets, straight or any other irregular geometry. Composites tends to be weaker and less stiff than continuous fibre composites, they are much less expensive. Particulate reinforced composites usually contains less reinforcements due to processing difficulties and brittleness. A fibre has a length that is much higher than its diameter. The length to diameter (l/d) ratio is known as the aspect ratio and can vary greatly in its field. Continuous fibre have really long aspect ratios, while discontinuous fibre have short ratios. Continuous-fibre composites normally have a standard orientation, while discontinuous fibre generally have a random orientation. Continuous-fibre composites are often made into laminates or sheets set by stacking single sheets of continuous fibre in different orientations to achieve the desired strength and stiffness properties with higher fibre volumes. Fibre produce high-strength composites due to their small diameter; they contain very less defects compared to the material produced in bulk. In general, the smaller the diameter of the fibre higher will be the strength but often the cost increases as the diameter becomes smaller. In addition, less-diameter high-strength fibre have greater flexibility and are easier to fabricate such as weaving or forming over radius. Typical fibre include glass and carbon, which may be continuous or discontinuous. The continuous phase is a matrix, which is a polymer or ceramic. Polymers have low strength and stiffness, metals have medium strength and stiffness but highly ductile, and ceramics have high strength and stiffness but are case brittle. The matrix performs several functions, including maintaining the fibre in the proper orientation and proper spacing and protecting them from abrasion. In the polymer and MMC that form a strong bond between the fibre and the matrix, the matrix transmits load from the matrix to the fibre through shear loading at the point of interface. In ceramic matrix composites, the objective is to increase the toughness value rather than strength and stiffness; therefore, a low strength bond is desirable. The type and quantity of the reinforcement shows the final properties.
Need for Composites:
A composite is something made from 2 or more components-in our case here, a fibre (Jute+ Bamboo) and a resin (PVC). Composites are not a new idea. Moses floated down the Nile in a basket made from papyrus coated with pitche. Papyrus form of the paper with a visible fibrous reinforcement would …
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