Graphene sheets have been found stronger and more flexible for bulletproof jackets compared to Kevlar and steel. University of Massachusetts and Rice University research team fired micro-bullets on 10-100 sheets of graphene to study the impact. Graphene has been tested for first time as armour and safety material.
Compared to steel, the stress tests found Graphene ten times better. In comparison to Kevlar, graphene sheets were twice better. Only issue was graphene was that the sheets were brittle. Same issue has been seen in carbon fiber as well but research teams have overcome that limitation.