Hi Amiklic,
Don't know the correct equations from memory, but you should be able to find them quickly on the internet; you need to calculate 'linear thermal expansion'.
Hmm, from memory, but I might be mistaken...
dL=alfa*dT*L
(in words: your change of length will be bigger when alfa is big, temp.difference is big or when the length is big)
Where
dL=change of length [m]
alfa=thermal rate of change (term?); unit unknown to me (probably 1/(deg.C*m)
L=length of your 'thing' that expands [m]
You should calculate dL for both your glaspane and your aluminium frame.
Let's say your frame is .5m * 1m in size; and it would heat up from 10deg.C to 60deg.C in the sun (not very unrealistic, I think, depending on the color; glass might have less dT)
So for glass: dL=alfa-glass*(60-10)1=.... m (depending on alfa)
and for alu frame: dL=alfa_alu(60-10)*1=....m (dep. on alfa_aluminium)
The dL's should be roughly the same, but they won't be. Therefore, stresses will occur within the glass and aluminium.
You can calculate the stresses with Hooke's Law:
sigma=epsilon*E
where sigma=stress (N/mm^2)
epsilon=strain (dL/L) (no unit)
and E=Elasticity-modulus of the material (for alu, from memory, about 80.000 N/m; steel is 210.000 N/m)
You know epsilon from the previous equation; E-modulus you can look up in a material's table; then you can calculate the stress (for either the glass or the aluminium, assuming 'the other' material has infinite stiffness (not very realistic); You could calculate it without this assumption, but for that I need to put my thinking cap on :-) )
This should get you on the way.
Peter,
The Netherlands.