2. Crystalline - regular structure and Noncrystalline (amorphous)-irregular structure.
or Traditional-clay, cement & glass and Advanced-newer high strength, high
temperature materials.
3. Advantages: hard, temperature resistance, corrosion resistance, inexpensive.
Disadvantages: brittle and hard to machine.
4. Ionic - tend to have high melting points & nondirectional strong bonds.
5. Covalent - tend to have lower melting points and weak bonds.
6. Ceramics have high melting points, tend to be brittle and have both ionic and covalent
bonds.
7. In ceramic materials, the atoms are not free to move under stress as they are in metals.
8. In glass, the lower energy bonding orbitals (valence band) and the higher energy
antibonding orbitals (conduction band) are different enough so that visible light is not
absorbed.
9. As the temperature increases, the vibrational amplitude increases for atoms in a material
which drives that atoms apart. In ceramics the bonds are stronger between atoms which
counteracts the tendency to expand.
10. Bones and teeth - hard, brittle and temperature resistant.
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