1. What made ceramics the first technology?
2. What are the two general classes of ceramics and how are they different?
3. What advantages and disadvantages do ceramics have over other materials?
4. What general properties do ionic materials have?
5. What general properties do covalent materials have?
6. What general properties do ceramic materials have?
7. Why are ceramics brittle and most metals not?
8. Why is glass transparent but a brick is not?
9. What causes thermal expansion in materials, and why do ceramic materials have small coefficients of expansion?
10. List the parts of your body that are ceramic materials. How do you know that they are?
1. Natural materials were available and so was fire.
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.