Ceramics

A **ceramic** is any solid that has been hardened by heat. Modern ceramics contain nonmetallic elements such as oxygen, carbon or silicon, but they can also contain metallic elements, such as aluminum or a transition metal. Ceramics can't be made into wires or flattened into thin sheets like metals. Ceramics are a lot different than metals. They can withstand extreme temperatures without melting or corroding. They are lightweight and normally very hard. Silicon carbide is a ceramic used for spacecrafts that is as hard as diamonds and can resist temperatures up to 2,000 degrees Celsius. Hot turbine engines are being built as well by either silicon carbide or silicon nitride.

In electrical conductors, electrons that flow as electric current tend to collide with the atoms of the conductor, transferring some of their kinetic energy to the conductor as heat that is eventually lost to the environment. The lost heat adds up when the energy is being carried over long distances. This means that some of the energy generated won't make it to the consumer. In the late 1980's, specially formulated ceramic compounds were found to carry energy for an indefinite length. The electrons in these conductors travel in pathways that avoid atomic collisions. Steady currents have been observed to persist for extended periods of time without apparent loss are called **superconductors** and they have zero electrical resistance. The current through them does not decrease, and they generate no heat.

Transmission of electrical energy is one obvious application for ceramic superconductors. The generated energy can be stored for later use in large circular loops of a superconducting material. Ceramics can't be drawn into wires. So they homogenize the superconducting ceramic starting materials with an organic thermoplastic. They warm the mixture up so it can be drawn into long fibers which are later baked into a medium. When the fibers cool, they become superconducting.

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