Properties of ceramics and glass

Ceramic Material Characteristics Ceramics and glasses are inorganic, nonmetallic materials consisting of metallic and nonmetallic elements bonded primarily with ionic and covalent bonds. These high strength bonds give rise to the special characteristics of these materials. They occupy a unique place in the spectrum of engineered materials offering many desirable alternatives to the metals and polymers in common usage. General Characteristics of Structural Materials Characteristic Ceramics Metals Polymers Density Low to High Low to High Low Hardness High Medium Low Tensile Strength Low to Medium High Low Compressive Strength High Medium to High Low to Medium Young’s Modulus Medium to High Low to High Low Melting Point High Low to High Low Dimensional Stability High Low to Medium Low Thermal Expansion Low to Medium Medium to High High Thermal Conductivity Medium Medium to High Low Thermal Shock Low Medium to High High Electrical Resistance High Low High Chemical Resistance High Low to Medium Medium Oxidation Resistance Medium to High Low Low Machinability Medium Low Medium There are wide variations in the properties of ceramics and glasses due primarily to differences in bonding and wide variations in chemical composition. However, as a materials class, the following characteristics are typical.   Low to moderate density compared to metals   High modulus of elasticity (stiffness)   Good strength retention at elevated temperatures   Resistant to high temperature creep   Dimensional stability   High compressive strength   Low to moderate tensile and shear strength   High hardness   Corrosion and oxidation resistant   Good electrical insulation properties   Wide range of thermal conductivity   Wide range of thermal expansion coefficient   Brittle   Low impact strength   Sensitive to thermal shock

Uses of Ceramics

Ceramic products are hard, porous, and brittle. As a result, they are used to make pottery, bricks, tiles, cements, and glass. Ceramics are also used at many places in gas turbine engines. Bio-ceramics are used as dental implants and synthetic bones. Given below are some other important uses of ceramics.

Uses of Whitewares

Whitewares find application in spark plugs, electrical insulators, laboratory equipments, crucibles, dishes, and high-class potteries.

Uses of Clay

Clay is the starting raw material for manufacturing bricks, tiles, terracotta, pottery, earthenwares, sewer, drain pipes, and covers for electrical cables.

Uses of Stonewares

Stonewares are used for constructing sanitary fixtures, such as sinks and bath tubs. Stonewares are also used in the construction of piping vessels, drainage pipes, underground cable sheathings, sewerage pipes, home pipes, absorption towers, valves, and pumps in the chemical industry. They are cheaper than many other construction materials but are rather fragile and once broken, they have no resale value.

Uses of Glass

The main use of glass is to make household glassware, decorative items, and optical lenses. Glasses are used for heat insulation purposes, for example, in ovens. Glass is used as an insulator in metal pipelines, in vacuum cleaners, and on the walls and roofs of houses. Glass is resistant to chemicals. As a result, it is used to filter corrosive liquids such as acids and acid solutions. It is also used for sound insulation. Safety glass is used in aircraft, automobiles, helicopter, and submarines. Glass can also be…

Question

1. define ceramics
2. 5 properties of ceramics

 

See also

Metals

Properties of metals

Wood

Properties of materials

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