The word “ceramic” includes a wide range of materials that are divided into two general categories: traditional and advanced. Of course, ceramics are also divided based on composition, manufacturing method and application.
How are ceramics classified
The word “ceramic” includes a wide range of materials that can be divided into two general categories. Traditional ceramics (pottery, structural clay products, clay-based refractories, cement, concrete, glass) include those materials that have been developed since the beginning of human civilization until today, which still includes a large part of the industry. The new world trend is towards advanced ceramics, which have often been developed in less than a century. The category of advanced ceramics that have technical, special, elegant and engineering applications can be generally divided into functional (electrical, magnetic, optical) and structural (at ambient temperature and high temperature) categories. However, the border between traditional and advanced ceramics is not clear. In addition to this general criterion, there are other criteria for dividing ceramics, some of which overlap with each other. In this part of the article, we examine some of the most important classification criteria for ceramic materials
Based on composition:
Oxide ceramics: These ceramics are mainly composed of metal oxides such as alumina, zirconia and silica. They are known for their strength, high hardness and resistance to wear and corrosion.
Non-oxide ceramics: These ceramics are composed of carbides, nitrides, borides and other compounds such as silicon carbide, aluminum nitride and titanium diboride. They are known for their strength, high hardness and resistance to wear and corrosion.
Composite ceramics: These ceramics consist of the combination of two or more different types of ceramic materials such as alumina and zirconia or ceramic and non-ceramic materials such as fiber reinforced ceramics. They are designed to combine the desired properties of different materials.
2- Based on crystal structure:
Crystal ceramics: These ceramics have a specific crystal structure and are classified based on the type of crystal structure such as cubic, tetragonal, or hexagonal. For example, we can mention alumina, zirconia and silicon carbide.
Glass ceramics: These ceramics have a combination of crystalline and glass phase. They are produced partially crystalline, and examples include lithium disilicate and lucite-reinforced glass ceramics.
Amorphous ceramics: These ceramics do not have a clear crystal structure and are often called glass. They are produced by cooling the melt and its examples are: silica and borosilicate glasses.
3- Based on properties:
Structural Ceramics: These ceramics are used for their high strength, stiffness and wear resistance and are commonly used in applications such as cutting tools, bearings and biomedical implants.
Electronic ceramics: These ceramics are used for their electrical conductivity, dielectric properties, and piezoelectric properties, and are commonly used in applications such as capacitors, sensors, and actuators.
Thermoceramics: These ceramics are used for their ability to withstand high temperatures and are commonly used in applications such as furnace linings, furnace components, and heat exchangers.
4- Based on the manufacturing method:
Traditional Ceramics: These ceramics are made using traditional manufacturing techniques such as casting and pressing and include products such as bricks, tiles and vessels.
Advanced Ceramics: These ceramics are made using more advanced manufacturing techniques such as chemical vapor deposition, sol-gel processing, and hot pressing, and include products such as cutting tools, biomedical implants, and electronic components.
Nanoceramics: These ceramics have nanoscale dimensions and unique properties such as strength, hardness and high thermal stability. They are produced using advanced techniques such as sol-gel and are used in applications such as catalysis, sensors and energy storage.
5- Based on physical condition
Ceramics can also be classified based on their physical state. In this method, the classification of ceramic material is divided into different types according to the way it is used:
Ceramic powder: Ceramic powder is a material that consists of ceramic particles. It is often used as a raw material for the production of ceramics through processes such as powder pressing, sintering and hot pressing.
Ceramic parts: Ceramic parts are three-dimensional objects made of ceramic materials. For example: ceramic tiles, ceramic dishes and glasses.
Ceramic fibers: Ceramic fibers are thin and flexible filaments made from ceramic materials. These materials are often used as reinforcement in composite materials, insulation in high temperature applications, and filters.
Ceramic coatings: Ceramic coatings are thin layers of ceramic material that are applied to the surface of a substrate. They can be used to improve substrate surface properties such as wear resistance, corrosion resistance and thermal insulation.
Ceramic composites: Ceramic composites are materials that are produced by combining two or more different types of ceramic materials or by combining ceramics with other materials such as metals or polymers. They can be used to achieve specific properties such as increased strength, improved wear resistance and reduced weight. Ceramic membrane: Ceramic membranes are thin and porous layers of ceramic materials used for filtration and separation. They can be used to remove contaminants from liquids and gases, or to separate different substances from a mixture