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A composite material (also called a composition material or shortened to composite) is a material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure. The new material may be preferred for many reasons: common examples include materials which are stronger, lighter, or less expensive when compared to traditional materials. More recently, researchers have also begun to actively include sensing, actuation, computation and communication into composites,〔(M. A. McEvoy and N. Correll. Materials that couple sensing, actuation, computation and communication. ''Science'' 347(6228), 2015. )〕 which are known as Robotic Materials. Typical engineered composite materials include: *Composite building materials, such as cements, concrete *Reinforced plastics, such as fiber-reinforced polymer *Metal composites *Ceramic composites (composite ceramic and metal matrices) Composite materials are generally used for buildings, bridges, and structures such as boat hulls, swimming pool panels, race car bodies, shower stalls, bathtubs, storage tanks, imitation granite and cultured marble sinks and countertops. The most advanced examples perform routinely on spacecraft and aircraft in demanding environments. ==History== The earliest man-made composite materials were straw and mud combined to form bricks for building construction. Ancient brick-making was documented by Egyptian tomb paintings. Wattle and daub is one of the oldest man-made composite materials, at over 6000 years old.〔Shaffer, G.D. "An Archaeomagnetic Study of a Wattle and Daub Building Collapse." ''Journal of Field Archaeology'', 20, No. 1. Spring, 1993. 59-75. (JSTOR. Accessed 28 January 2007 )〕 Concrete is also a composite material, and is used more than any other man-made material in the world. As of 2006, about 7.5 billion cubic metres of concrete are made each year—more than one cubic metre for every person on Earth.〔〕 * Woody plants, both true wood from trees and such plants as palms and bamboo, yield natural composites that were used prehistorically by mankind and are still used widely in construction and scaffolding. * Plywood 3400 BC by the Ancient Mesopotamians; gluing wood at different angles gives better properties than natural wood * Cartonnage layers of linen or papyrus soaked in plaster dates to the First Intermediate Period of Egypt c. 2181–2055 BC and was used for death masks * Cob (material) Mud Bricks, or Mud Walls, (using mud (clay) with straw or gravel as a binder) have been used for thousands of years. * Concrete was described by Vitruvius, writing around 25 BC in his ''Ten Books on Architecture'', distinguished types of aggregate appropriate for the preparation of lime mortars. For structural mortars, he recommended ''pozzolana'', which were volcanic sands from the sandlike beds of Pozzuoli brownish-yellow-gray in colour near Naples and reddish-brown at Rome. Vitruvius specifies a ratio of 1 part lime to 3 parts pozzolana for cements used in buildings and a 1:2 ratio of lime to pulvis Puteolanus for underwater work, essentially the same ratio mixed today for concrete used at sea.〔Heather Lechtman and Linn Hobbs "Roman Concrete and the Roman Architectural Revolution", ''Ceramics and Civilization Volume 3: High Technology Ceramics: Past, Present, Future'', edited by W.D. Kingery and published by the American Ceramics Society, 1986; and Vitruvius, Book II:v,1; Book V:xii2〕 Natural cement-stones, after burning, produced cements used in concretes from post-Roman times into the 20th century, with some properties superior to manufactured Portland cement. * Papier-mâché, a composite of paper and glue, has been used for hundreds of years * The first artificial fibre reinforced plastic was bakelite which dates to 1907, although natural polymers such as shellac predate it * One of the most common and familiar composite is fiberglass, in which small glass fiber are embedded within a polymeric material (normally an epoxy or polyester). The glass fiber is relatively strong and stiff (but also brittle), whereas the polymer is ductile (but also weak and flexible). Thus the resulting fiberglass is relatively stiff, strong, flexible, and ductile. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Composite material」の詳細全文を読む スポンサード リンク
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