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Hi Everybody,

I am hoping some of you might be able to help me out here.  We are working
on an exhibit about the glass industry and we have two phenomena that may be
quite difficult to demonstrate.


#1. Coefficent of Expansion.   If the exterior of a piece of glass cools
faster than the interior it can produce compressive forces strong enough to
shatter the material. I did a great experiment with this in my buddy's
kitchen when were in Jr. High.  We nuked some marbles in his mom's 1970's
vintage super powerful microwave and then we would drop them in ice-water
causing them to shatter.   This would not be terribly suitable for a museum
exhibit for lots of reasons, consumables, small parts, unsafe temperatures,
broken glass etc.  

#2 Viscosity. The viscosity of glass changes about 20 orders of magnitude
from its water like state when it is poured to its solid state at room temp.
Once again we are dealing with super high temps etc.

Any ideas you might have would be much appreciated.

Thanks,

Mike 

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