Ceramics Overview Ceramic is a term once thought to refer only to the art or technique of producing articles of pottery. Current usage has broadened to include items made of metal oxides, borides, carbides, nitrides, and the like, or compounds of such materials. A study of the word "ceramic" shows that it derives from the Greek word keramos, meaning "a potter" or "a pottery". However, the Greek word is related to an older Sanskrit root, meaning, "to burn"; as used by the ancient Greeks themselves, its primary meaning was simply "burnt stuff" or "burned earth". The fundamental concept contained in the term was that of a product manufactured through the action of fire or heat upon earthy materials. A traditional ceramic refers to products commonly used as building materials, or within the home and industry. Bricks, dinnerware, firebrick, and kiln furniture are good examples. Although there is a tendency to equate traditional ceramics with low technology, advanced manufacturing technologies, and new advances in materials development, are often used. Stiff competition among producers has caused manufacturing technologies to become more efficient and cost effective by using complex tooling and machinery, coupled with computer assisted process control. The oldest ceramic products originated from naturally occurring clay-bearing materials. Early potters found the plastic nature of clay (its workability or moldability) to be useful in forming shapes. In traditional ceramic formulations, clay acted as a plasticizer and binder for better shape forming, and to hold other ingredients together during later processing. Because of its tendency to exhibit a large amount of shrinkage during drying and firing, clay bodies were often modified by adding coarse ingredients that reduced shrinkage and cracking. In modern clay-based bodies, some typical non-clay ingredients are fine silica, alumina, coarse-ground fired product scrap called grog, and alkali minerals such as nepheline syenite that are added as fluxes. Fluxes have an effect of lowering a curing point, melting point, or maturing temperature of a ceramic mixture to make firing of a product possible at a lower temperature. The effect is similar to that of spreading salt on a winter sidewalk to melt the ice. Today’s ceramics are often hybrid combinations of traditional ceramic technology from the past, and new non-clay materials developed in university and government research programs, in addition to private industrial R&D efforts. High-tech ceramics being made for the space program, the electronics industry, and the automobile industry are being developed from materials not dreamed of only a few years ago, and which are becoming the foundations of many new businesses and industries. jxkelley/blog/index.php/ceramics-overview/
Posted on: Mon, 24 Jun 2013 07:03:19 +0000
Trending Topics
Recently Viewed Topics
© 2015