ceramic

Ceramic refers to a broad class of solid materials that are inorganic, nonmetallic, and typically crystalline, formed by the firing of natural or synthetic raw materials. Ceramics include traditional items such as pottery, bricks, tiles, and cement, as well as advanced engineering ceramics used in high-tech applications. They are usually hard, resistant to heat and chemicals, and good electrical insulators, but can be brittle.

Chemically, ceramics are compounds of metallic and nonmetallic elements. Common base chemistries include silicates (especially aluminosilicates), aluminates, zirconates, carbides, and nitrides. Their structures range from crystalline and polycrystalline to glassy (glasses) forms, with glazes often applied to create a glassy surface.

Categories vary by use and properties. Traditional ceramics cover household wares, sanitaryware, bricks, and tiles. Fine porcelains and bone china are highly engineered ceramics in the consumer market. Advanced or engineering ceramics include alumina, zirconia, silicon carbide, and silicon nitride, which offer high hardness, wear resistance, and thermal stability. Ceramics also play critical roles in electronics, serving as dielectrics, substrates, and piezoelectric or insulating components.

Processing typically involves shaping, drying, and firing. Shaping methods include wheel throwing, hand-building, slip casting, pressing, and extrusion. After shaping, items are dried and fired in kilns at temperatures chosen for the material, often followed by glazing to form a protective and decorative glassy layer. Sintering densifies the material and develops its final microstructure.

Applications span construction, tableware, and industrial components, to medical implants, energy devices, and electronic systems. Ongoing developments aim to improve toughness, reduce environmental impact, and expand manufacturability through methods such as additive manufacturing and composite approaches.