To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

4,5
Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
Added in 24 Hours
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.
.
Leo
Newton
Brights
Milds

From Wikipedia, the free encyclopedia

Furnace in fire clay.
Furnace in fire clay.

Fire clay is a range of refractory clays used in the manufacture of ceramics, especially fire brick. The United States Environmental Protection Agency defines fire clay very generally as a "mineral aggregate composed of hydrous silicates of aluminium (Al2O3·2SiO2·2H2O) with or without free silica."[1]

Properties

High-grade fire clays can withstand temperatures of 1,775 °C (3,227 °F), but to be referred to as a "fire clay" the material must withstand a minimum temperature of 1,515 °C (2,759 °F).[2] Fire clays range from flint clays to plastic fire clays, but there are semi-flint and semi-plastic fire clays as well. Fire clays consist of natural argillaceous materials, mostly Kaolinite group clays, along with fine-grained micas and quartz, and may also contain organic matter and sulphur compounds.

Fire clay is resistant to high temperatures, having fusion points higher than 1,600 °C (2,910 °F); therefore it is suitable for lining furnaces, as fire brick, and for manufacture of utensils used in the metalworking industries, such as crucibles, saggars, retorts and glassware. Because of its stability during firing in the kiln, it can be used to make complex items of pottery such as pipes and sanitary ware.

Chemical composition

The chemical composition typical for fire clays are 23-34% Al2O3, 50-60% SiO2 and 6-27% loss on ignition together with various amounts of Fe2O3, CaO, MgO, K2O, Na2O and TiO2.[2] Chemical analyses from two 19th-century sources, shown in table below, are somewhat lower in alumina[3][4] although a more contemporary source quotes analyses that are closer.[5]

Fire clay compositions
Thorpe[3] King[4] Shackelford[5]
Stonebridge Eisenberg I Eisenberg II Newcastle 1 Newcastle 2 Newcastle 3 N/A
SiO2 (%) 65.10 89.8 64.7 51.1 47.6 48.6 58.1
Al2O3 (%) 22.2 5.40 24.0 31.4 29.5 30.2 23.1
MgO (%) 0.18 0.09 0.40 1.54 0.71 1.91 1.00
CaO(%) 0.14 0.20 0.37 1.46 1.34 1.66 0.08
Iron Oxides (%) 0.18 0.09 0.40 4.63 9.13 4.06 2.40
K2O (%) 0.18 0.61 2.40 not given in the text

Extraction

Unlike conventional brick-making clay, some fire clays (especially flint clays) are mined at depth, found as a seatearth, the underclay associated with coal measures.

References

  1. ^ "Calciners and Dryers in Mineral Industries" (Background Information for Proposed Standards). U.S. Environmental Protection Agency. 1985: 3–48. EPA-450/3-85-025a{{inconsistent citations}} Cite journal requires |journal= (help)
  2. ^ a b Minerals Zone, World Mineral Exchange. Archived 2011-07-14 at the Wayback Machine Retrieved 2011-6-23.
  3. ^ a b Thorpe, Sir Thomas Edward (1890). A Dictionary of Applied Chemistry Volume I. Longmans Green & Company, London.
  4. ^ a b King, William B. (1878). King's Treatise on the Manufacture and Distribution of Coal Gas. self.
  5. ^ a b Shackelford, James F (2008). Ceramic and glass materials: structure, properties and processing. Springer. p. 121.
This page was last edited on 22 October 2020, at 20:34
Basis of this page is in Wikipedia. Text is available under the CC BY-SA 3.0 Unported License. Non-text media are available under their specified licenses. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. WIKI 2 is an independent company and has no affiliation with Wikimedia Foundation.