PorcelainMakingProcess.doc

Porcelain Ads by GoogleCeramic Injection Molding - Economic solutions for manufacture of complex component shapes. ()Alumina Ceramic Tubes - 2-3 Dia. Alumina Tubes for Furnace Quick delivery at ever low price ()Refractories Monolithic - World Class Products Castable, Monolithic, Refractories (www.prism.co.in) Background The term porcelain refers to a wide range of ceramic products that have been baked at high temperatures to achieve vitreous, or glassy, qualities such as translucence and low porosity. Among the most familiar porcelain goods are table and decorative china, chemical ware, dental crowns, and electrical insulators. Usually white or off-white, porcelain comes in both glazed and unglazed varieties, with bisque, fired at a high temperature, representing the most popular unglazed variety. Although porcelain is frequently used as a synonym for china, the two are not identical. They resemble one another in that both are vitreous wares of extremely low porosity, and both can be glazed or unglazed. However, china, also known as soft-paste or tender porcelain, is softer: it can be cut with a file, while porcelain cannot. This difference is due to the higher temperatures at which true porcelain is fired, 2,650 degrees Fahrenheit (1,454 degrees Celsius) compared to 2,200 degrees Fahrenheit (1,204 degrees Celsius) for china. Due to its greater hardness, porcelain has some medical and industrial applications which china, limited to domestic and artistic use, does not. Moreover, whereas porcelain is always translucent, china is opaque. Hard-paste or true porcelain originated in China during the Tang dynasty (618-907 A.D.); however, high quality porcelain comparable to modern wares did not develop until the Yuan dynasty (1279-1368 A.D.). Early Chinese porcelain consisted of kaolin (china clay) and pegmatite, a coarse type of granite. Porcelain was unknown to European potters prior to the importation of Chinese wares during the Middle Ages. Europeans tried to du