Crushed soda can .....
All you are talking about is a quantity of aluminum, regardless of the shape it takes. Crushed or not, the mass, volume of the metal and density of the metal are unchanged.
If you placed an empty, uncrushed soda can in water, and an identical crushed can in water they will both displace the same amount of water indicating that the volume of metal is unchanged, and the density of the metal is unchanged (D = m / V).
Billrussel42 is correct, electron1 is wrong. Electon1 is confusing the volume of the empty space in the can with the volume of the metal can itself.