What are scuba tanks made of?

Answer 1

Most Scuba tanks are filled with simple purified air.

However, some are filled with oxygen enriched air called 'nitrox' or (less commonly) a blend of helium, oxygen and nitrogen called 'trimix' or (even less commonly) helitrox or heliox.

Answer 2

There are many types.

Aluminum Scuba tanks are pressed from a slice of Aluminum.

Here is a video from YouTube (search scuba tank):

http://www.youtube.com/watch?v=qAgSU6BCpsY

Steel can be welded or rolled.

Answer 3

They are made usually from Aluminium or steel

Answer 4

These are approximates: 78% Nitrogen, 21% Oxygen, 1 % inert gases

Answer 5

Lead.