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Heating of a substance above the temperature at which a change of state would ordinarily take place without such a change of state occurring, for example, the heating of a liquid above its boiling point without boiling taking place; this results in a metastable state.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(1) The heating of a liquid above its boiling point (at a given pressure) or heating of a solid crystalline substance above the temperature of phase transition from one modification to another without the phase transition resulting. The transition of rhombic to monoclinic sulfur is an example of a transition from one modification to another. A superheated substance is in a labile, metastable state.

Crystalline substances cannot be superheated beyond the melting point, since all the absorbed heat goes into breaking bonds between the atoms or ions in the crystal lattice. For practically any phase transition that involves the absorption or release of heat, either slight superheating or slight supercooling must occur in order that the process occur at a finite rate. Superheated liquids are used in bubble chambers.

(2) The heating of a vapor above the saturation temperature while maintaining a constant pressure. Superheated water vapor is used widely in heat engineering.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Those calculations put the outer edge of the superheating zone roughly 10 to 50 solar radii from the surface.
The team's study presents the first direct measurements of the superheating of ice crystals in antifreeze protein solutions, according to Celik.
This is due to a phenomenon known as superheating. First, we have to understand what boiling is all about.
Saturated steam was then directed from a manifold into the four helically wound tubes where the superheating takes place.
This is good news for the compressor, which doesn't suffer from unsquashable liquid in the place where gas squashing takes place, and also good news for the evaporator manufacturer who gets to sell a larger evaporator to provide the necessary heat exchange surface to do this superheating.
* excessive, uncontrolled superheating of a low metal heel (including bridging of charge materials);
The researchers first simulated the response of a perfect crystal surface to a laser pulse and obtained clear evidence of superheating. Then they introduced a number of vacancies into the surface and found that superheating still occurred.
As a result, superheating (a major cause of reoxidation) can be avoided and fewer filter placement limitations exist.
Looking from the top of the furnace, it was evident that the silica refractory taper section had undergone a chemical attack or severe superheating. The refractory had undergone severe erosion and the silica dry vibratable hot face had melted.
Practical metallurgical tips to remedy shrinkage include: avoid superheating, minimize melt oxidizing conditions, keep carbon as high as possible, keep silicon on the lower end, pour as cold as possible, keep Mg as low as possible, optimize total rare earth additions and ensure the stream inoculant is sufficient.