Dating of domestic ceramics
What do all these very different materials have in common?From a chemical viewpoint, we define ceramics in terms of what they're not.People first started making ceramics thousands of years ago (pottery, glass, and brick are among the oldest human-invented materials), and we're still designing brand new ceramic materials today—things like catalytic converters for today's cars and high-temperature superconductors for tomorrow's computers.There's quite a big difference between age-old, general-purpose ceramics like brick and glass and modern, engineered ceramics that are sometimes designed for a single, specific purpose, such as filtering soot from a truck's dirty diesel engine or making a drill bit that lasts five times longer.Most modern engineered ceramics are metal oxides, carbides, and nitrides, which means they're compounds made by combining atoms of a metal with oxygen, carbon, or nitrogen atoms.So, for example, we have tungsten carbide, silicon carbide, and boron nitride, which are hard, cutting-tool ceramics; aluminum oxide (alumina) and silicon dioxide are used in making integrated circuits ("microchips"); and lithium-silicon oxide is used to make the heat-protective nose cones on space rockets.Picture by Warren Gretz courtesy of US Department of Energy/National Renewable Energy Laboratory (NREL) (picture id 6307388).
Ceramics like this are ancient materials—ones our ancestors would recognize—that have gradually found more and more uses as the centuries have worn on.
Examples include silicon carbide fibers in a silicon carbide matrix (Si C/Si C) with boron nitride at the interface between them—a material used in cutting-edge gas-turbine jet engines.
Photo: Advanced ceramics: Silicon and carbon fuse to form silicon carbide powder (left), which can be made into a hard and hard-wearing ceramic called silicon carbide that can survive high temperatures.
ou started your morning with ceramics—and they'll dominate your day.
Inside your brick, cement, and glass home, you woke to the quartz clock, washed in the tiled bathroom, breakfasted on pottery cups and bowls.