The preparation and processing of ceramics

Many of the characteristic properties of ceramics arise during manufacturing. Ceramic bodies are made by high-temperature firing (heating) routes that induce chemical reactions to take place, during which the final material is produced. 

Traditional ceramics are mainly made from mixtures of clays, silica (often extracted as flint) and feldspars (especially K2Al2Si60i6 and Na2Al2-SieOie). Low-quality structural products such as bricks and pipes are made directly from the appropriate clay. Higher-quality ceramics such as porcelain are made from carefully controlled amounts of specific clay, flint and feldspar. The use of these three major components has led to the name triaxial whitewares for these materials. 

Hard ceramic surface coatings on metalhc components can be made by heating the metal in an appropriate gaseous atmosphere. Reaction takes place at the metal surface and atoms from the gaseous component diffuse into the surface layer. Thus, if titanium is heated in nitrogen gas a layer of titanium nitride (TIN) will form on the surface as a hard layer. 

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