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A modern crucible used in the production of silicon ingots via the Czochralski process Smaller clay graphite crucibles for copper alloy melting. A crucible is a container in which metals or other substances may be melted or subjected to very high temperatures.
A Gooch crucible, named after Frank Austin Gooch, [1] is a filtration device for laboratory use (and was also called a Gooch filter [2]). It is convenient for collecting a precipitate directly within the vessel in which it is to be dried, possibly ashed , and finally weighed in gravimetric analysis .
Alchemical symbols were used to denote chemical elements and compounds, as well as alchemical apparatus and processes, until the 18th century. Although notation was partly standardized, style and symbol varied between alchemists.
When silicon is grown by the Czochralski method, the melt is contained in a silica crucible. During growth, the walls of the crucible dissolve into the melt and Czochralski silicon therefore contains oxygen at a typical concentration of 10 18 cm −3. Oxygen impurities can have beneficial or detrimental effects.
Ceramic BN crucible. Hexagonal BN (h-BN) is the most widely used polymorph. It is a good lubricant at both low and high temperatures (up to 900 °C, even in an oxidizing atmosphere). h-BN lubricant is particularly useful when the electrical conductivity or chemical reactivity of graphite (alternative lubricant) would be problematic.
A Hessian crucible is a type of ceramic crucible that was manufactured in the Hesse region of Germany from the late Middle Ages through the Renaissance period. They were renowned for their ability to withstand very high temperatures, rapid changes in temperature, and strong reagents .
The difference between the Bridgman [2] technique and Stockbarger [3] technique is subtle: While both methods utilize a temperature gradient and a moving crucible, the Bridgman technique utilizes the relatively uncontrolled gradient produced at the exit of the furnace; the Stockbarger technique introduces a baffle, or shelf, separating two ...
A pipeclay triangle is a piece of laboratory apparatus that is used to support a crucible being heated by a Bunsen burner or other heat source. It is made of wires strung in an equilateral triangle on which are strung hollow ceramic, normally fire clay, tubes. The triangle is usually supported on a tripod or iron ring.