Page 8 - Curriculum Visions Dynamic Book

But ceramics can be made to conduct electricity. One way is to dope them, as mentioned on page 6. Another way is to raise the temperature of the ceramic to very high levels. Finally, and by far the hardest method, is
to make ceramics become superconductors. Superconductors have almost no resistance
to the flow of electricity at extremely low
temperatures. This, too, is a result of metal
ions that are not centrally placed inside
their surrounding oxygen ions.
Why ceramics are brittle
brittleness means that a material goes from its elastic state to its breaking point without passing through a (plastic) stage in which it could change shape.
Ceramics are very strong under
compression, but they are very weak under
tension. Ceramics tend to fail because they are made
of crystals, and the weak points are between the
crystals. Once a fracture has started, it easily moves along the face of the crystal. This does not happen
in metals because they have imperfections in their crystals, which means that a fracture cannot easily
find a clear path to move along throughout the material. Instead, it fractures just a little and then stops. This is, in
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(Right) Integrated circuits contain doped ceramics that conduct electricity.