Can you make tank armor using Aluminium, Polymers, Styrofoam, Explosive Reactive Armor to stop NATO DP rounds and/or HEAT rounds maybe RPG-7?
Aluminium has a strength up to 800 N/mm2 (for its best Al-based alloys) while steels can go much higher... about 1400 N/mm2 if I recall well. The problem with aluminium is that is prompt to fatigue break which is not good with something vibrating like a rolling tank armor. Polymers are not strong enough unless you use composite materials, for ex. fibre glass or even better - carbon fibre reinforced. The problem is still that unlike steel, the strength is exceptionally high... in one direction - so pray for the impact to be mostly from this direction.
