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Forget about Kevlar: Liquid Body Armor Hardens on Impact

news.discovery.com

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Re: Forget about Kevlar: Liquid Body Armor Hardens on Impact

#11

Post by dbbolton »

pygy_ wrote: post #2

Non-Newtonian fluidics is at work here [0]. If you want to try it at home, mix cornstash with water (roughly 2 to 1) and create an Oobleck [1]. Guaranteed success with kids (and adults who remained young at heart). [0] http://en.wikipedia.org/wiki/Non-newtonian_fluid [1] http://en.wikipedia.org/wiki/Non-newtonian_fluid#Oobleck , http://www.google.fr/url?sa=t&rct=j&q=&esrc=s&#3... , http://www.google.fr/url?sa=t&rct=j…

"Cornstarch in water" was my first thought when reading this title, thanks to 7th grade science class.

Re: Forget about Kevlar: Liquid Body Armor Hardens on Impact

#13

Post by moylan »

Jtsummers wrote: post #4
ORioN63 wrote: post #3

It's actually quite old, the idea of using liquids as a body armor. The problem with implementation was the weight of the liquids. From this article, it has appeared that the problem was solved, since they mention that is a lot lighter and provides more freedom of movement.

http://news.discovery.com/tech/winter-olympics-body-armor.ht... Being used for skiers and mentions its use in body armor at the time (2010). I'm pretty sure I read an earlier article than that one as well, perhaps from 2006 or so but I can't find it. I can't tell from this new article if they've improved the fluid, or the method of application to kevlar is the novel part.

first i saw about non newtonian liquids was a british science entertainment show.

and about a year afterwards they began talking about using the same as armour. just stuck in my mind as the kids show came first.

from 2003. http://www.youtube.com/watch?v=JkS1ymQ73oc&feature=relat...

from 2004. http://www.technovelgy.com/ct/science-fiction-news.asp?newsn...

Re: Forget about Kevlar: Liquid Body Armor Hardens on Impact

#16

Post by icegreentea »

eslachance wrote: post #5

Question: If it hardens when it is disturbed, does it mean that it hardens if the wearer runs, for example? This would mean you still can't properly armor joints...

Shear thickening fluids have a non-linear relationship between shear rate and shear stress. Schematically, it's the green line in this graph [1]. By choosing your material carefully, you can minimize shear stress at 'running' speeds, and then sharply ramp it up to protect against faster projectiles.

[1] http://en.wikipedia.org/wiki/File:Shear_rate_vs._Shear_stres...

Re: Forget about Kevlar: Liquid Body Armor Hardens on Impact

#17

Post by AzAngel »

dbbolton wrote: post #11
pygy_ wrote: post #2

Non-Newtonian fluidics is at work here [0]. If you want to try it at home, mix cornstash with water (roughly 2 to 1) and create an Oobleck [1]. Guaranteed success with kids (and adults who remained young at heart). [0] http://en.wikipedia.org/wiki/Non-newtonian_fluid [1] http://en.wikipedia.org/wiki/Non-newtonian_fluid#Oobleck , http://www.google.fr/url?sa=t&rct=j&q=&esrc=s&#3... , http://www.google.fr/url?sa=t&rct=j…

"Cornstarch in water" was my first thought when reading this title, thanks to 7th grade science class.

Same here, but thanks to Mythbusters in my case.

Re: Forget about Kevlar: Liquid Body Armor Hardens on Impact

#18

Post by FreeFull »

pygy_ wrote: post #2

Non-Newtonian fluidics is at work here [0]. If you want to try it at home, mix cornstash with water (roughly 2 to 1) and create an Oobleck [1]. Guaranteed success with kids (and adults who remained young at heart). [0] http://en.wikipedia.org/wiki/Non-newtonian_fluid [1] http://en.wikipedia.org/wiki/Non-newtonian_fluid#Oobleck , http://www.google.fr/url?sa=t&rct=j&q=&esrc=s&#3... , http://www.google.fr/url?sa=t&rct=j…

Another example of a non-newtonian fluid (Except, in this case, shear-thinning instead of shear-thickening) would be ketchup.
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