Thermal expansion
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Thermal expansion is the tendency of matter to increase in size with increasing temperature. Matter generally increases in length, area, and volume, changing its size and density, in response to an in
Expansion joint in a road bridge used to avoid damage from thermal expansion.
Lord Kelvin, the namesake of the unit of measure
Thermal expansion of long continuous sections of rail tracks is the driving force for rail buckling. This phenomenon resulted in 190 train derailments during 1998–2002 in the US alone.
Drinking glass with fracture due to uneven thermal expansion after pouring of hot liquid into the otherwise cool glass
Zerodur
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Zerodur is a lithium-aluminosilicate glass-ceramic manufactured by Schott AG. Zerodur has a near zero coefficient of thermal expansion, and is used for high-precision applications in telescope optics,
Thermal expansion
…17.3 30.3 ~ 51.9 Steel Metal alloy 11.0 ~ 13.0 33.0 ~ 39.0 Depends on composition Titanium Metal 8.6 26 Tungsten Metal 4.5 13.5 Water Nonmetal 69 207 Zerodur Glass-ceramic ≈0.007–0.1 From 0 °C to 50 °C In solids When calculating thermal expansion it is necessary to consider whether the body is free to expand…
Opening of the ELT secondary mirror Zerodur blank mold containing the glass at first annealing at the Schott AG 4-meter blank annealing facility in Mainz, Germany.
The Keck II Telescope showing the segmented primary mirror made of Zerodur