Metal foam obliterates bullets – and that's just the beginning

April 6, 2016 by Matt Shipman

Composite metal foams (CMFs) are tough enough to turn an armor-piercing bullet into dust on impact. Given that these foams are also lighter than metal plating, the material has obvious implications for creating new types of body and vehicle armor – and that's just the beginning of its potential uses.

Afsaneh Rabiei, a professor of mechanical and at NC State, has spent years developing CMFs and investigating their unusual properties. The video seen here shows a composite armor made out of her composite metal foams. The bullet in the video is a 7.62 x 63 millimeter M2 armor piercing projectile, which was fired according to the standard testing procedures established by the National Institute of Justice (NIJ). And the results were dramatic.

"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," Rabiei says. "To put that in context, the NIJ standard allows up to 44 millimeters indentation in the back of an ." The results of that study were published in 2015.

But there are many applications that require a material to be more than just incredibly light and strong. For example, applications from space exploration to shipping nuclear waste require a material to be not only light and strong, but also capable of withstanding extremely high temperatures and blocking radiation.

The video will load shortly

Last year, with support from the Department of Energy's Office of Nuclear Energy, Rabiei showed that CMFs are very effective at shielding X-rays, gamma rays and neutron radiation. And earlier this year, Rabiei published work demonstrating that these metal foams handle fire and heat twice as well as the plain metals they are made of.

Now that these CMFs are becoming well understood, there could be a wide array of technologies that make use of this light, tough material. Armor, if you'll forgive the pun, barely scratches the surface.

Explore further: Metal foam handles heat better than steel, study finds

More information: Matias Garcia-Avila et al. Ballistic performance of composite metal foams, Composite Structures (2015). DOI: 10.1016/j.compstruct.2015.01.031

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21 comments

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Captain Stumpy
3.3 / 5 (12) Apr 06, 2016
the material has obvious implications for creating new types of body and vehicle armor – and that's just the beginning of its potential uses
i would be much more excited to see how this applied to space technology and micrometeorite impacts, etc...

they have a great test gun to check out how it would react

so put more up about "applications from space exploration"!
And earlier this year, Rabiei published work demonstrating that these metal foams handle fire and heat twice as well as the plain metals they are made of.
Hey!
cops and firefighter applications too!

that is really really cool IMHO
Composite metal foams (CMFs) are tough enough to turn an armor-piercing bullet into dust on impact
this is likely just a metal jacketed round and not a DP round

.
.
just sayin
bschott
Apr 06, 2016
This comment has been removed by a moderator.
Captain Stumpy
3.2 / 5 (9) Apr 06, 2016
dumbasfuck

If you whine cry bohoo

... bs wants to be in a "lobotomized predicament" to explain away her having almost a whole 3 IQ points rounding up the nearest whole number.

just sayin
@full-of-bs
i fixed that for you

WOW!
... i have another groupie who wants to follow me around and make disparate comments about my posts because she doesn't understand science, physics or the difference between evidence and conjecture (like analogy - you know, like your super-magnetic cancer machine?)

LMFAO

troll on, groupie!
and thank you for your posts

you only bring attention to your own inadequacies and pseudoscience beliefs

why is that important, you ask?
https://www.youtu...EwjBXlZE

compose
Apr 06, 2016
This comment has been removed by a moderator.
bschott
1 / 5 (7) Apr 06, 2016
troll on, groupie!
and thank you for your posts


Cheers!

you only bring attention to your own inadequacies and pseudoscience beliefs


I love our chats that everyone can read, although your take on how they are viewed is, like most of your "understandings" ....wrong.

why is that important, you ask?


Well...I didn't...but as usual you cannot discern reality from your own fairy tale world in which you make a difference, know things and people respect you. Did the voices ask you any other questions?
Captain Stumpy
4.2 / 5 (5) Apr 06, 2016
The composite armors already have appearance of foam
@zephir
some do... true, but not all
https://en.wikipe...e_armour
edshort4
5 / 5 (8) Apr 07, 2016
Odd and disappointing that neither the video nor any still photo showed what the metal foam plate looked like after the bullet event was over.
Mark Thomas
4.3 / 5 (6) Apr 07, 2016
"i would be much more excited to see how this applied to space technology and micrometeorite impacts, etc."

Hard to believe bschott went off the deep end over such a harmless comment, there must be some bad blood there. I for one agree with you Captain Stumpy. Better body armor is great, but perhaps we could develop entirely new capabilities with CMFs in space.

kaf
1 / 5 (1) Apr 07, 2016
Yeah, but can it be produced with wind or solar power? What about that?
mzmadmike
5 / 5 (3) Apr 07, 2016
7.62 X 63 is commonly known as .30-06. M2 is copper jacketed ball ammo, not armor piercing. Still impressive, but not an accurate description.
antigoracle
3 / 5 (2) Apr 07, 2016
i would be much more excited to see how this applied to space technology and micrometeorite impacts, etc...

Well, if those micrometeorites shattered into thousands of micro micrometeorites...hmm... it would make for a more "exciting" time in space.
Da Schneib
5 / 5 (3) Apr 07, 2016
this is likely just a metal jacketed round and not a DP round

.
.
just sayin
It says right out it's a 7.62x63 143-grain AP round. I think that's a "black tip." I don't know what a "DP" round is. You prolly know more than I do, but do check this out. Pretty sure from the "armor piercing" in the article that it's not just an ordinary FMJ round.
Da Schneib
5 / 5 (3) Apr 07, 2016
7.62 X 63 is commonly known as .30-06. M2 is copper jacketed ball ammo, not armor piercing. Still impressive, but not an accurate description.
According to Wikipedia, there are both M2 and M2 armor piercing; see https://en.wikipe...ormance:

In an effort to increase accuracy some snipers resorted to use of the heavier .30-06 M2 armor-piercing round...
Da Schneib
5 / 5 (4) Apr 08, 2016
With some more research, I was able to definitively identify the exact bullet from the Wikipedia article. It's this one:

Armor Piercing, M2 (1939-1954): This cartridge is used against lightly armored vehicles, protective shelters, and personnel, and can be identified by its black bullet tip. Bullet is flat base, weight 163-168 grains. Defense against the M2 projectile by name is one of the performance standards for Type IV body armor.
The fact that it's the standard bullet for testing body armor, as mentioned in the article, definitively confirms that this is not standard ball ammo. Here's the listing for the ball ammo, from the same article:

Ball, M2 (1937-1954): With a 9.7 g (150-grain) bullet based on the profile of the M1906, this cartridge incorporated the gilding-metal jacket of the M1 projectile combined with a slightly heavier, pure-lead core. It had a higher muzzle velocity than either of the earlier cartridges.


This is from the same article linked above.
Da Schneib
5 / 5 (3) Apr 08, 2016
Oh, and obviously I was wrong, it's not 143 grains. I misread another reference. Which is what I get for not checking Wikipedia in the first place.
Captain Stumpy
4.2 / 5 (5) Apr 08, 2016
It says right out it's a 7.62x63 143-grain AP round
@Da Schneib
yeah, an AP round is an armour piercing, but there are different types
mostly, it is a lead core with metal jacket high velocity round, but you can also find them with steel, carbide or other posts inside for penetration, which is different than the standard AP round, which brings us to DP
I don't know what a "DP" round is
Depleted uranium - which is also an armour piercing round, and far, far more effective than just the standard AP round
You prolly know more than I do
maybe, maybe not. just had a little experience in a Bradley
Pretty sure from the "armor piercing" in the article that it's not just an ordinary FMJ round
that is what i wanted to know, because the standard is just a high velocity FMJ (which may have a post in it, but may not as well, depending - it varies... and standard NATO ammo is Ball and FMJ)
Captain Stumpy
4 / 5 (4) Apr 08, 2016
Oh, and obviously I was wrong, it's not 143 grains
@Da Schneib
i wouldn't worry about it

i am waiting for some feedback from a couple people on this. might take some time with their schedules though.

.

.

.

Hard to believe bschott went off the deep end over such a harmless comment
@Mark Thomas
Yeah. there is a lot of bad blood
bs is still mad because i won't accept *analogy and personal claims that can't be verified* as equivalent to scientific evidence for his super-duper-magnetic-cancer-cure-all that can't pass FDA approval
Da Schneib
5 / 5 (3) Apr 08, 2016
The Wikipedia article is pretty definitive, Cappy.

They used the same round that's used as a standard for testing body armor. And that's the Armor Piercing, M2, not the Ball, M2. I expect both are FMJ rounds; I doubt it has a post in it, I don't think that came out until long after this round was designed in the 1930s. This one is the one known as the "black tip," according to the Wikipedia article.

In any case, this stuff outperforms the standard test by quite a lot given the permitted deformation on the back of the armor.

Lighter vehicles can go faster with the same engine, and farther on a tank of gas, and are more maneuverable. And you can compromise and get all those things, and still have more protection than solid armor can give you.
Da Schneib
5 / 5 (4) Apr 08, 2016
My wife just asked how it would perform against EFP IEDs. I'm still thinking about that. I suspect better than solid armor by quite a lot; because it's foamed, it probably will have much better ability to disperse the penetrator material than solid armor does. It's like non-explosive reactive armor, in which a layer of dispersant material, like rubber, is placed between two sheets of armor steel, dispersing an incoming penetrator or shaped charge jet before it hits the inner layer.
Protoplasmix
5 / 5 (1) Apr 10, 2016
I'm guessing that the slow blade penetrates the foam...

...and fear is still the mind killer...
EyeNStein
not rated yet May 05, 2016
I wonder if CMF technology could replace the structural stainless steel in advanced tokamak designs such as ARC, and enable really high confinement fields (up to 23T) to be used?
Especially if useful (neutron moderator-multiplier) and exceptional toughening metals like Beryllium could be used in the mix.

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