Ceramics
Ceramics is one of the oldest materials. It has a lot of favorable characteristics, including strength, heat resistance, environmental and chemical safety, and great aesthetic potential in items created from it, all of which contribute to its widespread use.
Ceramics are goods manufactured from clay (or clay-like substances) with or without mineral additions, molded, and fired. The most common use for ceramics is decorative ceramic tiles.
Consumer properties
As factors that shape the consumer properties and quality of ceramic household goods, the same ones are for glass products: the type of ceramics, the method of molding, and the type of decoration.
Depending on the structure, fine ceramics (glassy or fine-grained shard) and coarse (coarse-grained shard) are distinguished. Porcelain, semi-porcelain, faience, majolica, and coarse pottery are the most common varieties of fine ceramics.
Porcelain – has a densely sintered shard of white color (sometimes with a bluish tint) with low water absorption (up to 0.2%), emits a high melodic sound when struck, and can be translucent in thin layers. The edge of the side or the base of the product is not coated with glaze due to the double burning of the product.
Determine the difference between hard and soft porcelain. Tableware, tea and coffee utensils, and other common items are hard porcelain.
Kaolin, sand, feldspar, and other additions are raw materials in the making of porcelain.
Semi-porcelain in properties occupies an intermediate position between porcelain and faience, its shard is white, water absorption is 3 ~ 5%.
Faience goods
Those shards are white with a yellowish hue and have a porosity of 9-12 percent. Faience goods are totally coated with a colorless glaze because of their great porosity. Pottery ceramics have a red-brown hue and a high porosity (red-burning clays) (water absorption up to 18 percent ).
Colorless glazes are the products, which can be with colorful clay paints – engobe. The assortment is full of kitchen and household utensils (pots for roasting, milk jugs) and decorative items.
Ceramic Properties
A chemical link holds the atoms in ceramic materials together. Covalent and ionic chemical bonding is the most common in ceramic materials. The bonding of atoms in covalent and ionic bonding is substantially stronger than in metallic bonding. As a result, metals are ductile while ceramics are brittle in general. Ceramic materials are employed in a wide range of applications due to their diverse characteristics. The majority of ceramics are:
- hard,
- wear-resistant,
- brittle,
- refractory,
- thermal insulators,
- electrical insulators,
- nonmagnetic,
- oxidation resistant,
- prone to thermal shock, and
- chemically stable.
Ceramic materials’ thermal characteristics
1. It is heat resistant. For example, alumina melts at temperatures reaching 1800°C, much above the melting point of metallic materials.
2. The coefficient of thermal expansion ratio describes how much a material expands when the temperature rises by one degree Celsius. Ceramics have a thermal expansion coefficient that is less than half that of most steels.
3. Insulating materials, glass, refractories, abrasives, and enamels are all examples of traditional ceramics. Metal oxides, carbides, borides, nitrides, and silicates are among them. Tungsten carbide, Silicon carbide, Beryllia, Zirconia, Alumina, and Magnesia are some of its examples.