Concept and classification of ceramics

First, the concept and classification of ceramics

1. The concept of ceramics:

According to the composition, materials are generally divided into metal materials, inorganic non-metallic materials and organic materials. In 1968, the American Academy of Sciences defined ceramics as "inorganic nonmetallic materials or articles". Ceramics is a material closely related to human life and production. With the continuous development of productivity and the continuous improvement of the level of science and technology, the concept and category of "ceramics" given by various historical stages are constantly changing, especially after the emergence of advanced ceramics, the definition focusing on traditional ceramics is no longer applicable. In a broad sense, ceramic materials refer to all other materials in addition to organic and metallic materials, that is, inorganic non-metallic materials. In a narrow sense, ceramic materials mainly refer to polycrystalline inorganic non-metallic materials, that is, inorganic non-metallic materials synthesized by high temperature heat treatment. The analysis of ceramic products by modern analytical technology shows that ceramic is a mixture composed of several crystalline and glass phases, each of which has many different compositions. These components mainly belong to inorganic non-metallic materials. Therefore, some countries refer to solid products composed of inorganic non-metallic materials as basic components as ceramics. In the world, inorganic nonmetallic materials are often called ceramic materials.

2. Classification of ceramics:

People are used to dividing ceramics into two categories, namely traditional ceramics and advanced ceramics. Traditional ceramics are natural silicate minerals as raw materials (clay, feldspar, quartz, etc.), after grinding processing, molding, sintering and other processes to obtain products, so it is also called silicate ceramics, such as daily ceramics, art ceramics and industrial ceramics (high-voltage electric porcelain for the power industry, chemical industry corrosion resistant chemical ceramics, etc.). Construction ceramics and sanitary ceramics for the building industry). With the difference, people will be the modern development of a variety of ceramics collectively known as advanced ceramics, advanced ceramics is the use of high purity synthetic compounds (such as AL2O3.Zr02.Sic.SiC.Si3N4.BN), through the appropriate structural design, accurate stoichiometry, appropriate forming methods and firing system, Inorganic non-metallic materials obtained by processing.