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

Asked by: Mark Farren, by email

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.

Read more:

• Are atoms expanding as the Universe expands?
• What is the Universe expanding into?

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