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New Metal Foam Armor Obliterates Bullets To Dust On Impact (discovery.com)
HughPickens.com writes: Discovery Magazine reports that researchers at North Carolina State University have developed a super strong armor material that literally turns bullets to dust upon impact. The armor plating is made in part from composite metal foams, or CMFs, which are both lighter and stronger than traditional metal plating used in body and vehicle armor. The armor -- only an inch thick -- features a ceramic strike face, Kevlar backing, and CMFs in the energy-absorbing middle layer. "We could stop the bullet at a total thickness of less than an inch, while the indentation on the back was less than 8 millimeters," says Afsaneh Rabiei. "To put that in context, the NIJ standard allows up to 44 millimeters indentation in the back of an armor." CMFs are very effective at shielding X-rays, gamma rays and neutron radiation. Other applications include space exploration and shipping nuclear waste which both require a material to be not only light and strong, but also capable of withstanding extremely high temperatures and blocking radiation. A video shows a 7.62 x 63 millimeter M2 armor-piercing projectile that was fired using standard testing procedures established by the Department of Justice for evaluating armor types.
For those who are confused, 7.62x63mm is the metric designation for a .30-06.
Stopping a 30-06 M2 isn't actually that hard. A half inch of steel will do it easily. If that steel is of the Abrasion Resistant (AR) variety of decent grade (like AR400 or AR500), it will hold up to thousands of shots with virtually no wear.
Of course, a half inch steel plate is very heavy and not the sort of thing an infantryman wants to have to wear. Which is why Type IV plates are made of exotic materials like this.
This armor is actually a laminate. The impact surface is ceramic and very hard. The metal foam is in the middle and it distributes the load over a wider area. The Kevlar layers are presumably there to catch any fragments that penetrate. Actually, it sounds an awful lot like the Chobham that we use on the M1 Abrams.
And, since it is finally on topic, here is a link to a video with a bunch of bullet impacts in slow motion. It is amazing!.
See that "Preview" button?
The article is kinda pointless if it doesn't mention the weight of the armor, which is kinda the whole point.
cheaper counter method would be to pack some bullets with some cheap poisonous dust.
That method has already been used, and countered
Isn't that what Robin is for?
I saw some documentary that sort of explained this.
It was about SWAT teams and storming rooms and how they like to move quickly in patterns the person in the room can't predict.
The movement creates a kind of cognitive problem for the adversary in the room which causes them to target center of mass. This kind of increases the utility of body armor because the adversary "can't" target their heads very well, making any shots likely to hit the body armor instead of more exposed extremities.
It seemed kind of reasonable to me, although I wonder if there's a "in real life" aspect to this that might weaken the tactic, like recoil or muzzle climb tending to cause point of impact on multiple shots to rise. My guess is that the movement of the SWAT guys is enough of a deterrent for secondary shots to not hit them.
The other possibly confounding factor would be just the random nature of poor marksmanship or the "spray and pray" effect. A presumably unskilled shooter may simply fire a lot of rounds in a way that disregards any aiming or target motion, possibly increasing the likelihood of some impact. My guess is that part of the goal of SWAT movement is rapid lateral movement relative to the adversary, making it difficult for the adversary to achieve a wide enough field of fire for even random shooting to be effective.
It does make me wonder if special forces type soldiers have a specifically trained countermeasure to defend against trained, skilled people storming a room, such as sweep firing from extreme lateral angles, combined with their own movement, to at least reduce any advantage in attacker methods.
Why don't you go wank to a war movie? You complain about someone that doesn't care much for the military - is there some requirement to have a hard-on for military to post on /.? He didn't even say something about not protecting the military - just that he doesn't think it is a priority.
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Space armor is mostly using a spaced (!) armor with relatively lightweight materials combined with a spall-liner. The reason is that using something that can stop the (natural) high speed projectiles a spacecraft can be bombarded with isn't technically feasible due to weight. For smaller (but still high-speed) projectiles a spaced design is a good solution.
However you are wrong that metal foam isn't a space armor, the reason you list isn't true as this foam is part of sandwich - the actual catching/slowing down of the projectile is done by the ceramic strike plate. If one want to make a stronger anti-meteorite armor for space metal foam is a good candidate for several reasons including weight, strength and (using the right materials) extra protection against radiation.
But I don't see what's new about this - metal foams have been used for composite armor for a while now.
Harder jackets and higher speeds would be the next logical steps but will probably mean more lined barrels. I'd guesstimate 20 years out unless we've a major conflict with lots of money invested. If that's the case, expect 2-3 years and a total of about 5 for the new weapons to be really effective. That's all assuming this is something that can be scaled up into production sizes to suit. I obviously haven't read the article but tech like this languishes until needed for large-scale conflicts and then gets incorporated quickly and prices drop as well as production times are lowered.
Man is never so motivated as when he's trying to kill someone or to stop someone from killing him.
"So long and thanks for all the fish."
Not good enough. A foot-thick plate of this stuff still wouldn't protect me from my ex-wife's "Stare Of Death".
That bitch could galvanize a battleship with just a look. You guys know the look I'm talking about.
Just cruising through this digital world at 33 1/3 rpm...
After the medieval knight with full plate armor fell out of use because of cheap pikemen and the pistol,
I thought it was the crossbow, actually. The longbow could nail a knight to a tree, but required a lot of training and strength. The crossbow could do the same but could be learned quickly. Early firearms were about on a par with a crossbow both for handling accuracy and rate of fire (though they had other advantages - and far more room for technical improvement with time).
Is my impression wrong?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
so soldiers are going to wear gas masks? to protect against poisonous dust sent through exploding bullets?
No, they'll choose die in their millions from poisoned bullets all the time screaming 'what can we possibly do about this unstoppable threat'.
Do you have any idea how defence works?