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Materials for different uses - OCR GatewayDifferent materials

Materials include glass and clay ceramics, polymers, metals and composite materials. They have different physical properties, which make them suitable for different uses.

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Different materials

Different have different , but they may also have some properties in common. The table summarises some of the typical properties of glass and clay ceramics, and metals.

Glass ceramicsClay ceramicsMetals
AppearanceTransparentOpaqueShiny
Melting pointHighHighHigh
Malleable or brittleBrittleBrittleMalleable
Ability to conduct electricityPoorPoorGood
Ability to conduct heatPoorPoorGood
Appearance
Glass ceramicsTransparent
Clay ceramicsOpaque
MetalsShiny
Melting point
Glass ceramicsHigh
Clay ceramicsHigh
MetalsHigh
Malleable or brittle
Glass ceramicsBrittle
Clay ceramicsBrittle
MetalsMalleable
Ability to conduct electricity
Glass ceramicsPoor
Clay ceramicsPoor
MetalsGood
Ability to conduct heat
Glass ceramicsPoor
Clay ceramicsPoor
MetalsGood

Glass ceramics

Glass shatters when it is hit or dropped
Figure caption,
Glass shatters when it is hit or dropped

Glass is made by melting sand, then allowing the liquid to cool and solidify. Glass is and , but it is .

Clay ceramics

Clay ceramics include brick, china and porcelain. They are made by heating clay to high temperatures, which causes to form and join together. Clay ceramics are often coated with a glaze, which hardens on heating to form a hard, smooth, and waterproof layer.

Metals

Brick is strong in compression - it resists being squashed
Figure caption,
Brick is strong in compression - it resists being squashed

are and , so they can be bent into shape or made into wires without shattering. Unlike glass and clay ceramics, metals are good electrical .