Why ceramics have higher boiling point than metals?
Answers
Answer:
A material in order withstand high temperature needs a high melting point. A hig melting point is got based on the nature of the bond. A bond which requires low energy to dissociate and a bond which requires high energy to dissociate will form low melting and high melting materials. As melting means conversion from solid (closely packed) to liquid (loosely packed or dissociated form), there is in need of energy to loosen or dissociate.
Ceramics usually have ionic bond with some covalent character. These bonds corresponds to high bond energies making ceramics high temperature melting materials and giving the ability to withstand high temperatures.
There are also some high temperature melting metals called refractory metals like Titanium, Molybdenum, Tungsten. But the ease of processing, availability and wide range of applications makes ceramics potential high temperature materials.