Introduction
The metal ceramic materials are widely used in various engineering fields due to their excellent properties. Generally, the definition of metal ceramic materials is inorganic materials composed of metal and ceramic, which can be divided into three types: i) metal composite ceramics, ii) metallic-ceramic ceramics and iii) crystalline ceramics.
1. Metal Composite Ceramics
Metal composite ceramic, also known as coating ceramic, is a material that combines two phases of metal and ceramic. Its most important feature is that it has a porous and non-porous structure. The porous structure of metal-ceramic composite material adopts a metallic or ceramic coating on its surface, which maintains the natural metallic or ceramic properties of the material.
2. Metallic-ceramic Ceramics
Metallic-ceramic ceramic is a novel material that combines metal and ceramic through a special process. The properties of metallic-ceramic ceramic can be divided into four categories: i) mechanical properties, ii) electrical properties, iii) optical properties and iv) thermal properties.
i) Mechanical Properties: The mechanical properties of metallic-ceramic ceramic are superior to metals and even better than ceramics. It has the properties of robustness, wear resistance and toughness.
ii) Electrical Properties: Metallic-ceramic ceramic has good electrical insulation and electric conductivity, especially in high-frequency applications.
iii) Optical Properties: Optical properties of metallic-ceramic ceramics also show excellent performance due to their high refractive indices.
iv) Thermal Properties: Metallic-ceramic ceramics have low coefficient of thermal expansion and melting point.
3. Crystalline Ceramics
Crystalline ceramics are materials composed of metal and ceramic particles. They are characterized by their nano-sized particles and the presence of metal atoms in the crystal structure. Due to their small feature sizes and metal atoms, their properties at nano-level are quite different from those of metal or ceramic materials. Firstly, crystalline ceramics have higher mechanical strength than metal and ceramic materials. Secondly, they have better electrical and thermal properties, and higher corrosion resistance than metal and ceramic materials.
Conclusion
Metal ceramic materials have advantages over metal and ceramic materials. These advantages include excellent mechanical properties, electrical properties, optical properties and thermal properties. Crystalline ceramics are a special type of metal ceramic material with unique properties at nano-level. The application of metal ceramic materials have wide ranging applications in various engineering fields, especially in high temperature, wear resistant and corrosion resistance applications.
