eli5, What is the difference between aluminum and space grade aluminum?

Question

Is it just marketing or is there an actual structural difference?

In: 807

Answer 1

There’s not “space grade”. Aluminum is very often alloyed (mixed) with other minerals to alter its physical properties. There are a number of alloys that are commonly used in aerospace applications (sometimes called “aerospace grade” alloys), typically designated by a grade number: 2024 might be used for the skin of a plane, and 7075 for the structural parts of the fuselage.

Different grades have different properties, like how rigid or bendable they are, how they handle weathering and corrosion, how easily they can be welded, etc.