Fine ceramics
Fine ceramics are also called high-performance ceramics and high-tech ceramics. According to its use, it can be divided into two categories: engineering ceramics and functional ceramics. The former mainly uses their high hardness, high melting point, abrasion resistance and corrosion resistance, and is also called structural ceramics; the latter mainly uses their physical properties such as light, sound, electricity, heat, and magnetism, and is also called electronic ceramics. According to chemical composition can be divided into oxide type and non-oxide type. The former includes various oxides and oxyacid salts; the latter includes nitrides, carbides, and borides. The former type is generally used for functional ceramics, and the latter type is used for engineering ceramics. Some varieties are used to manufacture engine parts, auto parts, televisions, hair dryers, fire alarms, high-temperature extrusion molds, etc. It can also be used to manufacture high-temperature nozzles, suitable for the needs of national defense.
The main difference between fine ceramics and traditional ceramics
In terms of raw materials, it breaks through the boundary of traditional ceramics with clay as the main raw material. Special ceramics generally use oxides, nitrides, silicides, borides, carbides, etc. as their main raw materials. The main difference is that various chemical compositions, shapes, particle sizes and distributions of fine ceramic raw materials can be precisely controlled.
In terms of composition, the composition of traditional ceramics is determined by the composition of clay, so ceramics of different origins and kilns have different textures. Since the raw materials of special ceramics are pure compounds, the composition is determined by the artificial ratio, and the quality of its properties is determined by the purity and technology of the raw materials, not by the place of origin.
In the preparation process, advanced methods such as isostatic pressing, injection molding and vapor deposition are often used in molding to obtain a uniform and relatively accurate green body size, and the green body density has also been greatly improved; the sintering method has broken through the traditional ceramics. Furnace is the limit of the main production methods, and vacuum sintering, protective atmosphere sintering, hot pressing, hot static pressing, reaction sintering and self-propagating high temperature sintering are widely used.
In terms of performance, special ceramics have different special properties and functions, such as high strength, high hardness, corrosion resistance, conductivity, insulation, and special functions in various aspects of magnetism, electricity, light, sound, and biological engineering, so that they can High temperature, machinery, electronics, aerospace, and medical engineering are widely used.
The fundamental difference between fine ceramics and traditional ceramics is that they can be prepared from the selection of raw materials, and the subsequent manufacturing process methods can be strictly controlled, so that ceramic materials with different performance requirements can be manufactured in practice.
