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1. Composite Materials
I. Expensive Composite materials (also called composition materials or shortened to composites) are materials 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.
II. The new material may be preferred for many reasons: common examples include materials which are stronger, lighter or less when compared to traditional materials.
III. 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)
IV. 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 counter tops. The most advanced examples perform routinely on spacecraft in demanding environments.
2. Engineering Materials
I. Engineers deal with the science and technology of producing materials that have properties and shapes suitable for practical use.
II. Activities of these engineers range from primary materials production, including recycling, through the design and development of new materials to the reliable and economical manufacturing for the final product.
III. Metals - Metals are materials that are normally combinations of "metallic elements". These elements, when combined, usually have electrons that are non-localized and as a consequence have generic types of properties. Metals usually are good conductors of heat and electricity. They are also quite strong but deformable and tend to have a lustrous look when polished.
IV. Ceramics - Ceramics are generally compounds between metallic and nonmetallic elements and include such compounds as oxides, nitrides, and carbides. Typically they are insulating and resistant to high temperatures and harsh environments.
V. Plastics - Plastics, also known as polymers, are generally organic compounds based upon carbon and hydrogen. They are very large molecular structures. Usually they are low density and are not stable at high temperatures.
VI. Semiconductors - Semiconductors have electrical properties intermediate between metallic conductors and ceramic insulators. Electrical properties are strongly dependent upon small amounts of impurities.
VII. Composites - Composites consist of more than one material type. Fiberglass, a combination of glass and a polymer, is an example. Concrete and plywood are other familiar composites. Many new combinations include ceramic fibres in metal or polymer matrix.