Fused silica is a high-purity form of silica (SiO2) that is produced by melting pure silica and then cooling it rapidly to form a glass. The resulting material is highly transparent and has a low coefficient of thermal expansion, making it an important material in various scientific and technological applications.
Fused silica has a very high melting point (around 1713°C) and is highly resistant to thermal shock, making it an excellent material for high-temperature applications. It is also highly resistant to chemical attack, making it useful in harsh chemical environments.
One of the most important properties of fused silica is its high transparency in the ultraviolet (UV) to infrared (IR) range. This makes it a valuable material for optical applications such as lenses, mirrors, and prisms. Its low coefficient of thermal expansion also makes it useful in precision optics applications where dimensional stability is critical.
Fused silica is also used as a substrate material for growing thin films of other materials such as silicon and germanium. It is also used in the manufacturing of various electronic components, including microchips and transistors.
Another important application of fused silica is in the production of fiber optic cables. The high purity and low attenuation of fused silica make it an excellent material for transmitting light over long distances with minimal signal loss.
|Apparent porosity ( % )||0|
|Density ( g cm-3 )||2.2|
|Useful optical transmission range||180 - 2500 nm|
|Water absorption - saturation ( % )||0|
|Dielectric strength ( kV mm-1 )||25-40|
|Volume resistivity ( Ohmcm )||1018 @ 25°C|
|Compressive strength ( MPa )||1100|
|Hardness - Knoop ( kgf mm-2 )||820|
|Hardness - Vickers ( kgf mm-2 )||1000|
|Shear strength ( MPa )||70|
|Tensile modulus ( GPa )||72-74|
|Tensile strength ( MPa )||48|
|Coefficient of thermal expansion ( x10-6 K-1 )||0.54 @ 20-1000°C|
|Melting point (°C )||1715|
|Specific heat ( J K-1 kg-1 )||670-740 @ 25°C|
|Thermal conductivity ( W m-1 K-1 )||1.46 @ 20°C|
|Upper continuous use temperature ( °C )||1100-1400|