Ceramics are inorganic, nonmetallic materials. Ceramics include tiles, bricks, plates, glass, and toilets and are found in watches (quartz tuning forks-the time keeping devices in watches), snow skis (piezoelectric-ceramics that stress when a voltage is applied to them), automobiles (sparkplugs and ceramic engine parts), and phone lines. They can also be found on space shuttles, appliances (enamel coatings), airplanes (nose cones). Depending on their method of formation, ceramics can be dense or lightweight. Typically, they will demonstrate excellent strength and hardness properties; however, they are usually brittle in. They can also be formed to serve as electrical conductors or insulators. Some ceramics, like superconductors, also display magnetic properties.
Ceramics are generally made by taking mixtures of clay, earthen elements, powders, and water and shaping them into desired forms. Once the ceramic has been shaped, it is fired in a high temperature oven known as a kiln. Often, ceramics are covered in decorative, waterproof, paint-like substances known as glazes.
The properties of ceramic materials, like all materials, are dictated by the types of atoms present, the types of bonding between the atoms, and the way the atoms are packed together. The two most common chemical bonds for ceramic materials are covalent and ionic. The bonding of atoms together is much stronger in covalent and ionic bonding than in metallic. That is why, generally speaking, metals are ductile and ceramics are brittle. Due to ceramic materials wide range of properties, they are used for a multitude of applications. In general, most ceramics are:
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hard,
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wear-resistant,
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brittle,
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refractory,
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thermal insulators,
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electrical insulators,
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nonmagnetic,
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oxidation resistant,
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prone to thermal shock, and
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chemically stable.