Why Graphene Armor Doesn’t Exist and What it Might Look Like
Mountains of papers and articles have been written on the subject of graphene armor. From serious studies in scientific journals, to speculative and sensational click-bait, there’s far too much to review here. But all of it rests on the shakiest and weakest of foundations. Here’s why:
The theoretical strength of a material is essentially the strength of that material’s atomic bonds. Thus the theoretical strength of a pane of common soda-lime silicate glass is approximately 40,000MPa. This over-states the actual measurable strength of that type of glass by roughly two orders of magnitude; defects in a real-world pane of glass, which act as crack nucleation points, reduce its strength to roughly 100MPa. Even the strongest fiberglass whiskers, which are as defect-free as modern technology can make them, almost never exceed a 6,000MPa tensile strength – ~15% of the material’s theoretical strength.
All other materials are similar in this regard. The theoretical strength of polymers and ceramics is typically >10x their actual measured strength. (And perfect ceramics that attain their theoretical strengths would be almost completely fracture-proof.) The same is largely true of metals, though this is slightly more complicated as a metal alloy is not a homogeneous substance. In any case, martensite’s strength ceiling is well over 3600MPa, and yet most martensitic steel alloys clock in at roughly half that value.
