What are Ceramic Materials and Their Uses?
Ceramics are typically hard and chemically stable materials with valuable applications. Traditional and advanced are the main types of ceramics, and the advanced ceramics industry is a rapidly growing industry with important functional applications.
Introduction to Ceramics
Ceramics are special materials with many applications in almost all the engineering disciplines. But their importance has often been underestimated due to the fact that many people believe that ceramics are all about pottery and tiles. Today's ceramics industry is one of most rapidly advancing concerns in many parts of the world including USA, where the advanced ceramic market is over 13 billion US dollars. Ceramic industry began to expand as a modern industry with the attribution of new techniques and knowledge gained in the 1970s. Since then it has also been one of most competitive industries in the market.
Ceramic materials are special because of their properties. They typically possess high melting points, low electrical and thermal conductivity values, and high compressive strengths. Also they are generally hard and brittle with very good chemical and thermal stability. Ceramic materials can be categorized as traditional ceramics and advanced ceramics. Ceramic materials like clay are categorized as traditional ceramics and normally they are made of clay, silica, and feldspar. As its name suggests, traditional ceramics are not supposed to meet rigid specific properties after their production, so cheap technologies are utilized for most of the production processes.
Ball clay, China clay, Feldspar, Silica, Dolomite, Talc, Calcite and Nepheline are the common materials used for most of the ceramic products. Each raw material contributes a certain property such as dry strength, plasticity, shrinkage, etc. to the ceramic body. Therefore, by careful selection of materials, desired properties are acquired for the final output. Powder preparation is a major consideration in the ceramic industry. Surface area, particle size and distribution, particle shape, density, etc. each have their own effect on production. Powder has to be prepared to meet required particle size, particle shape, and other requirements for a particular industry. Milling is done to get the desired particle size. Unlike in the ,advanced ceramics industry the purity of ceramic powder is not an issue in traditional ceramics.
The traditional ceramics industry originated long ago. Even thousands of years ago it was a well established practice in many parts of the world. Today there are many divisions of this industry. Pottery, tableware, sanitaryware, tiles, structural clay products, refractories, blocks, and electrical porcelain are some of the products of traditional ceramics.