MIT makes compressed graphene sponge material that is
20 times less dense than steel but 10 times stronger, light as
stryofoam but stronger than steel.:
"A team of researchers at MIT has designed one of the strongest lightweight materials
known, by compressing and fusing flakes of graphene, a two-dimensional form of carbon.
The new material, a sponge-like configuration with a density of just 5 percent, can have a
strength 10 times that of steel.
In its two-dimensional form, graphene is thought to be the strongest of all known
materials. But researchers until now have had a hard time translating that
two-dimensional strength into useful three-dimensional materials."
See:
http://www.nextbigfuture.com/2017/01...ne-sponge.html