Does All Metals Expand When Heated?

Contrary to intuition, however, not all materials expand when heated - some actually contract. Recent research on these so-called negative thermal expansion (NTE) materials has led to the discovery of alloys exhibiting unexpectedly large thermal contraction.

Which metal does not expand on heating?

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.

Do all metals expand on heating?

All pure metals have positive coefficient of thermal expansion, that they expand on heating and contract on cooling. But a few compounds of some metals may display negative thermal coefficient, that is they contract on heating and expand on cooling.