Whats is the difference between crystalline and non-crystalline ceramics?

[qwerty0123]

whats is the difference between crystalline and non-crystalline ceramics?

 

[Astronuc]

By non-crystalline, is one referring to amorphous ceramics such as glass?

 

[qwerty0123]

By non-crystalline, is one referring to amorphous ceramics such as glass?

yeah

 

[Panthera Leo]

Non crystalline solids or in other words "Amorphous" solids do not have any long-range atomic order... Amorphous solids do have short range order but lack long range structural periodicity.

http://en.wikipedia.org/wiki/Amorphous_solid

But crystalline solids have very long-range orders.

Quote from WikiPedia:
"A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions"

http://en.wikipedia.org/wiki/Crystals

A simple example is Quartz (Amethyst, Citrine etc = SiO2 crystal) vs Silica-Glass (SiO2 Amorphous)

A very rapid cooling of molten SiO2 may result in formation of the amorphous glass because enough time has not been made available for the molecules to get in order. (this is very simplified view :p )
While a slow cooling of the melt is more likely to produce the crystalline SiO2.

To distinguish these two types of SiO2; The best optical way, if the solids are transparent is looking for Air Bubbles in the solids. Crystalline form usually lacks any Bubble BUT the amorphous type will certainly have MASSIVE and Uncountable number of tiny or large bubbles visible under 10X magnification!

By the way, One fun fact; Did you know Opal (the gemstone) is an amorphous SiO2 ! So strictly speaking its a kinda glass.


Best Wishes :)