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Many of our modern technologies require materials with unusual combinations of properties that cannot be met by the conventional metal alloys, ceramics, and polymeric materials. Composite Material, substance which is made up of a combination of two or more different materials. A composite material can provide superior and unique mechanical and physical properties because it combines the most desirable properties of its constituents while suppressing their least desirable properties. Composite materials usually consist of synthetic fibers embedded within a matrix, a material that surrounds and is tightly bound to the fibers. The most widely used type of composite material is polymer matrix composites (PMCs). PMCs consist of fibers made of a ceramic material such as carbon or glass embedded in a plastic matrix. Typically, the fibers make up about 60 percent of a polymer matrix composite by volume. Metal matrices or ceramic matrices can be substituted for the plastic matrix to provide more specialized composite systems called metal matrix composites (MMCs) and ceramic matrix composites (CMCs), respectively.

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Addisu Workiye graduated from Addis Ababa University, School of Mechanical and Industrial Engineering.

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