Does anyone know where I can find a chart (or formula) concerning the deflection of metals subjected to high vacuum (10-6 torr or lower) pressure?

My main concern is using aluminum 6061 T6, and 304 stainless steel plates.

I know it exerts 14.77 psi of negative pressure. So a 30” x 24” plate would have 10,634.4 pounds of force applied to it.

For example if I was making a chamber 30” x 24” x 12” is there a simple way of figuring out the minimum allowable wall thickness of the material to avoid collapsing, or metal fatigue problems?

Thank you

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The critical element would be the 24x30 plate. You would look up in a good stress analysis handbook the maximum moment for a plate that size, using the 14.7 psi as a uniform pressure and assume for conservatism that the plate is simply supported on 4 edges. Roarke's "Stress and Strain" is a good reference. Knowing the moment, you then solve for the the thickness of the plate(6M/bt^2=stress), using the allowable compressive stress for the material of that size, and give due considerstion to local buckling stresses per Code. You might want to check deflection under this load if the bulge is too much for your situation. The steel is stronger than the aluminum, and for a given thickness, the aluminum will deflect about 3 times more than the steel.