Aluminium
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Aluminium is a lightweight material and is used to make bed frames and headboards because it can be easily shaped and transported. Aluminium is also an inexpensive metal, making the production of aluminium-based beds relatively cheap.
Aluminium naturally generates a protective oxide coating and is highly resistant to corrosion.
Iron
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Iron is the most widely used metal in the world and is considered more of a heavyweight metal; certainly heavier than Aluminum. As a result, Iron bed frames can sometimes be difficult to move.
Iron is prone to rust, so products made of this metal should be treated with rust-preventing solutions.