Page 44 - Curriculum Visions Dynamic Book

(Far right and above)
Ceramics used for generating electricity from sunshine.
Another way is to cast a slurry of the ceramic onto a tape made of a nonstick material such as Teflon. This slurry then sets, and the tape and the ceramic are rolled up into a reel for later use.
Sintering
In ordinary ceramics heating causes some of the ends of the clays to turn glassy, and that helps hold the ceramic together. It also begins to fill in any pores and so makes the ceramic denser. This is called “sintering,” and it is the process that strengthens and hardens the ceramic.
Sintering does not happen in advanced ceramics because they are not made of clays, and because the particles are so much smaller.
When advanced ceramics are heated, the particles literally change shape, with some material moving
to places where particles are touching. The touching parts then get fused together.
Ceramics and electronics and optics
We know about ceramics as insulators. They are used, for example, to keep electric wires away from the utility poles that support them. But in the last half century people have discovered a wide range of other ways for ceramics to be used in our everyday lives – although we might not notice it. For example, a simple toaster may now contain a small piece of ceramic that controls when it switches off. A ceramic may store charge inside your computer (it is called a ceramic capacitor); it may be used in your electronic scales (where the change in shape of a ceramic sends out an electrical signal); or ceramic may be found in loudspeakers and in microphones (where it is used
as a powerful magnet). Ceramics are also made into lasers and optical switches. In fact, the list of ceramic applications is proving to be both exciting and almost endless.
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