Ceramic engineering

Ceramic engineering is the science of creating objects from inorganic, non-metallic materials. This is done using either heat or precipitation reactions on high-purity chemical solutions at lower temperatures. The term includes the purification of raw materials, the study and production of chemical compounds, their formation into components, and the study of their structure, composition, and properties.

Ceramic materials may have a crystalline or partly crystalline structure, with long-range order on atomic scale. Glass-ceramics may have an amorphous or glassy structure. They can be formed from a molten mass that solidifies on cooling or chemically synthesized at low temperatures using methods such as hydrothermal synthesis.

Ceramic materials are used in the fields of materials engineering, electrical engineering, chemical engineering and mechanical engineering. Ceramics are heat resistant, so they can be used for tasks in which materials like metal and polymers are unsuitable.

Ceramic engineering, like many sciences, evolved from a different discipline. Materials science and engineering is commonly considered the origins of ceramics engineering.

Abraham Darby first used coke in 1709 in Shropshire, England, to improve the yield of a smelting process. Coke is now widely used to produce carbide ceramics. Potter Josiah Wedgwood opened the first modern ceramics factory in Stoke-on-Trent, England, in 1759. Austrian chemist Carl Josef Bayer, working for the textile industry in Russia, developed a process to separate alumina from bauxite ore in 1888. The Bayer process is still used to purify alumina for the ceramic and aluminum industries. Brothers Pierre and Jacques Curie discovered piezoelectricity in Rochelle salt c. 1880. Piezoelectricity is one of the key properties of electroceramics.

E.G. Acheson heated a mixture of coke and clay in 1893, and invented carborundum, or synthetic silicon carbide. Henri Moissan also synthesized silicon carbide and tungsten carbide in his electric arc furnace in Paris about the same time as Acheson. Karl Schröter used liquid-phase sintering to bond or "cement" Moissan's tungsten carbide particles with cobalt in 1923 in Germany. Cemented (metal-bonded) carbide edges greatly increase the durability of hardened steel cutting tools. W.H. Nernst developed cubic-stabilized zirconia in the 1920s in Berlin. This material is used as an oxygen sensor in exhaust systems. The main limitation on the use of ceramics in engineering is brittleness.

The military requirements of World War II encouraged innovation, which created a need for high-performance materials and helped speed the development of ceramic science and engineering. Throughout the 1960s and 1970s, new types of ceramics were developed in response to advances in atomic energy, electronics, communications, and space travel. The discovery of ceramic superconductors in 1986 has spurred research to develop superconducting ceramic parts for electronic devices, electric motors, and transportation equipment.

There is an increasing need in the military sector for high-strength, robust materials which have the capability to transmit light around the visible (0.4–0.7 micrometers) and mid-infrared (1–5 micrometers) regions of the spectrum. These materials are needed for applications requiring transparent armor. Transparent armor is a material or system of materials designed to be optically transparent, yet protect from fragmentation or ballistic impacts. The primary requirement for a transparent armor system is to not only defeat the designated threat but also provide a multi-hit capability with minimized distortion of surrounding areas. Transparent armor windows must also be compatible with night vision equipment. New materials that are thinner, lightweight, and offer better ballistic performance are being sought.