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New chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pure chemicals are used.
Vitrification (from Latin vitrum 'glass', via French vitrifier) is the full or partial transformation of a substance into a glass, [1] that is to say, a non-crystalline or amorphous solid. Glasses differ from liquids structurally and glasses possess a higher degree of connectivity with the same Hausdorff dimensionality of bonds as crystals: dim ...
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.
The change from supercooled liquid to glass occurs at a temperature called the glass transition temperature, which depends on both cooling rate and the amount of water dissolved in the magma. Magma rich in silica and poor in dissolved water is most easily cooled rapidly enough to form volcanic glass.
Frit. A frit is a ceramic composition that has been fused, quenched, and granulated.Frits form an important part of the batches used in compounding enamels and ceramic glazes; the purpose of this pre-fusion is to render any soluble and/or toxic components insoluble by causing them to combine with silica and other added oxides. [1]
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.
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.
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.