Comment: The material is irrelavant if you have a maximum use pressure.

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In reply to comment: No, many are aluminum (see in situ)

The material is irrelavant if you have a maximum use pressure.

What would be the point of putting explosives in a sealed container? The whole point of the cooker is there is no need for large quantities of traditional explosives. All that is needed is a chemical reaction that causes expansion and shrapnel material. In that small confined space there does not need to be much expansion.