2 - Technologies

Ceramics are produced from powdered raw material by a sintering process. Ceramics obtained in this way are polycrystalline, an aggregation of fine crystalline grains, and grain boundaries inevitably exist. They play an important role in the sintering process and have a large influence on chemical and physical properties.The process begins with the mixing of powdered raw materials and additives by weight. When the starting material is a powder, the synthesis, or refining, of the powder is one of the most important processes affecting the quality of the final product. After the mixing, an organic resin - a temporary binder material - is added to the raw material powder. Then the powder is compacted in a definite form. Prior to sintering, it is necessary to get rid of the organic resin used for forming by heating the compact at a low temperature. The formed product is sintered at a high temperature and becomes dense through contraction. Sintering is the consolidation of a powder by means of prolonged use of elevated temperature, which is, however, below the melting point of any major constituents of the ceramic.