Aluminum Plates and Load Conditions

There are many varying conditions and mechanical values to factor in first, in order to calculate a plate thickness, which you didn't provide. For example: What is the type of aluminum being used (type of alloy, it's tensile strength, etc.). What types of loads will the specific aluminum be subjected to? What kind of environment will this aluminum be in? (temperature range, humidity, etc.) Should the CTE (co-efficient of thermal expansion) be considered? If you could provide more information about the problem, I'm sure your question could be answered.

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