Thinner annealed glass is typically more resistant to thermal shock. One company representative told me that thickness does not matter with respect to thermal shock resistance for tempered glass, and I'm not easily finding references to this in the literature for any compositions. Thank you for references and discussion that explores whether thickness effects the thermal shock resistance of tempered glass, and (potentially) why not?
For this question, one does not need a literature study, which is perfectly clear from Hooke's law: tension in material is directly proportional to deformation. The thicker the material, the greater the temperature differences at the surface and in the interior of this material during warm-up or cooling and, therefore, the greater the deformations. In other words, the thicker the material, the higher the tensions created by the temperature change.
The statement that the thickness of the tempered glass has no influence on its thermal shock resistance is absurd.
I agree completely with the answer above. The stress induced during rapid cooling (thermal shock) is directly proportional to the temperature difference between the surface and the center of the object. Tempering has no affect on that difference for the same quenching conditions. The thicker the piece, the greater the difference and the higher the stress.
Now if you mean, does tempering alter the degree of thermal shock needed to cause fracture, then the answer is yes. The stress at the surface has to become tensile for fracture to occur, which means overcoming the compressive stress induced by tempering. But thickness still matters, since the tensile stress at the surface is still directly dependent on the temp. difference between the surface and the center. (I assume we are talking about a sheet of glass here.)
We actually did this experiment in a lab course back when I was still teaching. Samples were held at different temps. and then quenched by dropping into room temp. water. The tempered glass had to be heated to a higher temperature to induce cracking than an identical piece of non-tempered glass. If you want to increase fracture resistance by thermal shock, this does mean that tempering will help. So will lowering the thermal expansion coefficient of the glass, i.e. borosilicate versus soda-lime-silica glass.
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