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Glass-ceramics exhibit advantageous thermal, chemical, biological, and dielectric properties as compared to metals or organic polymers. [87] The most commercially important property of glass-ceramics is their imperviousness to thermal shock. Thus, glass-ceramics have become extremely useful for countertop cooking and industrial processes.
Soda–lime glass (for containers) [2] 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. ...
Silanization is the attachment of an organosilyl group to some chemical species. Almost always, silanization is the conversion of a silanol-terminated surface to a alkylsiloxy-terminated surface. This conversion confers hydrophobicity to a previously hydrophilic surface.
A physical change involves a change in physical properties. Examples of physical properties include melting, transition to a gas, change of strength, change of durability, changes to crystal form, textural change, shape, size, color, volume and density. An example of a physical change is the process of tempering steel to form a knife blade.
Fused silica can be made from almost any silicon-rich chemical precursor, usually using a continuous process which involves flame oxidation of volatile silicon compounds to silicon dioxide, and thermal fusion of the resulting dust (although alternative processes are used). This results in a transparent glass with an ultra-high purity and ...
The structural theories of glass formation only consider the relative ease of glass formation. Materials which form glasses under a moderate cooling rate are called good glass formers, those that require a rapid cooling rate are called poor glass formers and those that require extreme cooling rates are referred to a non-glass formers.
Vitrified sand is a type of natural glass, contrasted with manufactured glass in which soda ash or potash are added to lower the melting point. Pure quartz melts at 1,650 °C (3,002 °F). There are several natural processes that produce more or less melted sand and one man-made form: Fulgurite is sand fused by a lightning bolt hitting sand.
Chemical strengthening results in a strengthening similar to toughened glass. However, the process does not use extreme variations of temperature and therefore chemically strengthened glass has little or no bow or warp, optical distortion, or strain pattern. This differs from toughened glass, in which slender pieces can be significantly bowed.