Are there any materials that don't expand on heating? © iStock

Are there any materials that don’t expand on heating?

Thermal expansion is the tendency for a material to change it's characteristics due to external temperature.

Asked by: Mark Farren, by email

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At extremely low temperatures, silicon and germanium expand with cooling rather than heating. The effect is called negative thermal expansion. The same applies to carbon fibres and certain exotic glass-like materials and metal alloys. In 2003, scientists at Michigan State University published research into combining such materials with conventional substances that expand when heated. The resulting bodies would therefore withstand sudden heating or cooling without breaking.

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