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Glass-ceramic from the LAS system is a mechanically strong material and can sustain repeated and quick temperature changes up to 800–1000 °C. The dominant crystalline phase of the LAS glass-ceramics, HQ s.s., has a strong negative coefficient of thermal expansion (CTE), keatite-solid solution as still a negative CTE but much higher than HQ s ...
A high strength glass-ceramic cook-top with negligible thermal expansion. Glass-ceramic materials share many properties with both glasses and ceramics. Glass-ceramics have an amorphous phase and one or more crystalline phases and are produced by a so-called "controlled crystallization", which is typically avoided in glass manufacturing.
Ultra-high-temperature ceramics (UHTCs) are a type of refractory ceramics that can withstand extremely high temperatures without degrading, often above 2,000 °C. [1] They also often have high thermal conductivities and are highly resistant to thermal shock, meaning they can withstand sudden and extreme changes in temperature without cracking or breaking.
Chemical or thermal treatments can increase the strength of glasses, and the controlled crystallization of certain glass systems can produce transparent glass-ceramics. Alstom Grid Research & Technology (Stafford, UK), produced a lithium disilicate based glass-ceramic known as TransArm, for use in transparent armor systems with continuous ...
The T g is clearly influenced by the chemistry of the glass. For example, addition of elements such as B, Na, K or Ca to a silica glass, which have a valency less than 4, helps in breaking up the network structure, thus reducing the T g. Alternatively, P, which has a valency of 5, helps to reinforce an ordered lattice, and thus increases the T ...
Solid-state chemistry reveals the fundamental connection between microstructure and properties, such as localized density variations, grain size distribution, type of porosity, and second-phase content, which can all be correlated with ceramic properties such as mechanical strength σ by the Hall-Petch equation, hardness, toughness, dielectric ...
Optical glass refers to a quality of glass suitable for the manufacture of optical systems such as optical lenses, prisms or mirrors.Unlike window glass or crystal, whose formula is adapted to the desired aesthetic effect, optical glass contains additives designed to modify certain optical or mechanical properties of the glass: refractive index, dispersion, transmittance, thermal expansion and ...
Unless stated otherwise, the properties of fused silica (quartz glass) and germania glass are derived from the SciGlass glass database by forming the arithmetic mean of all the experimental values from different authors (in general more than 10 independent sources for quartz glass and T g of germanium oxide glass). The list is not exhaustive.