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The extremely low coefficient of thermal expansion, about 5.5 × 10 −7 /K (20–320 °C), accounts for its remarkable ability to undergo large, rapid temperature changes without cracking (see thermal shock). Phosphorescence in fused quartz from an extremely intense pulse of UV light in a flashtube, centered at 170 nm
Borosilicate (low expansion, similar to Pyrex, Duran) Glass wool (for thermal insulation) Special optical glass (similar to Lead crystal) Fused silica Germania glass Germanium selenide glass Chemical composition, wt% 74 SiO 2, 13 Na 2 O, 10.5 CaO, 1.3 Al 2 O 3, 0.3 K 2 O, 0.2 SO 3, 0.2 MgO, 0.01 TiO 2, 0.04 Fe 2 O 3
Aluminium oxynitride is optically transparent (≥80% for 2 mm thickness) in the near-ultraviolet, visible, and mid-wave-infrared regions of the electromagnetic spectrum. It is four times as hard as fused silica glass, 85% as hard as sapphire, and nearly 115% as hard as magnesium aluminate spinel. It can be fabricated into transparent windows ...
As quoted in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition.CRC Press. Boca Raton, Florida, 2003; Section 4, Properties of the Elements and Inorganic Compounds; Physical Properties of the Rare Earth Metals
A number of materials contract on heating within certain temperature ranges; this is usually called negative thermal expansion, rather than "thermal contraction".For example, the coefficient of thermal expansion of water drops to zero as it is cooled to 3.983 °C (39.169 °F) and then becomes negative below this temperature; this means that water has a maximum density at this temperature, and ...
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A Assuming an altitude of 194 metres above mean sea level (the worldwide median altitude of human habitation), an indoor temperature of 23 °C, a dewpoint of 9 °C (40.85% relative humidity), and 760 mmHg sea level–corrected barometric pressure (molar water vapor content = 1.16%).
Depending on the operating environment, they must be resistant to thermal shock, be chemically inert, and/or have specific ranges of thermal conductivity and of the coefficient of thermal expansion. The oxides of aluminium ( alumina ), silicon ( silica ) and magnesium ( magnesia ) are the most important materials used in the manufacturing of ...