3. Graphene-based armor could stop bullets by becoming harder than diamonds - scien...

Graphene-based armor could stop bullets by becoming harder than diamonds - scientists have determined that two layers of stacked graphene can harden to a diamond-like consistency upon impact, as reported in Nature Nanotechnology.

From my other post

You are being pedantic now, so let's get pedantic!

Standard 9mm bullet: 115 grain bullet at 1246 fps has ~396 ft-lbs of energy, (7.45g at 380fps has ~537 joules of energy) maximum (bullet will slow down even if pointed straight down because it is going faster than terminal velocity.

Assuming a completely elastic collision between the objects (bullet and vest on a person...ie no lost momentum due to deformation or transferred energy to heat, sound, etc.), Then assuming a 200lb person in the vest, then the bullet will make them move with an after collision velocity of 0.1 ft/s.

If we assume that the collision stops the bullet in exactly 1", then the acceleration would be -9.31x106 ft/s/s, which gives us a force acting against the bullet at 1.53x105 lbft/s/s, which converts to 4.76x103 lbf (or 21.2 kN).

A 9mm bullet has a cross section area of 9.90x10-2 in2, so that force spread ONLY over area of bullet would produce a pressure of 48.0 KSI (or 330 MPa)... But if it is spread over a greater area, such as what you would expect with a piece of armor, let's say over the area of a half a normal torso so about 9" diameter, then you only get 74.8 psi, a very reasonable kick so to speak, but only about 5x the pressure that atmosphere is pushing on every part of your skin at all times.

This of course is a single example based on a common bullet, not some gigantic tank round, but something you'd reasonably expect to be stopped by today's bullet proof vest... I'd say the vest wearer is at little worry for internal organ damage...

You ever see that Vibranium shield that Captain America uses? Yeah that is complete nonsense.

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