For a graphic demonstration of this sort of effect add water to a few =

tablespoons of cornflour until you have a paste on the wet side of =

stiff and then try stirring it with a spoon at various speeds. The =

properties are quite mind boggling.

        http://www.timesonline.co.uk/article/0,,2087-2340507,00.html

"
SOLDIERS are to begin trialling a futuristic =93liquid armour=94 that is =

worn like ordinary clothing but turns into a rigid shield as soon as =

it is hit by bullets or shrapnel.
The armour consists of material impregnated with liquid silica that =

has been modified using nanotechnology. It is designed as a flexible =

alternative to the current military armour, which consists of Kevlar =

material reinforced by heavyweight ceramic plates.


The American army hopes to use the liquid armour =97 which has been =

likened to the skin of cyborgs in films such as Terminator and =

RoboCop =97 in a new combat outfit that will enter service in 2010. =

British troops are also examining the concepts behind the armour, the =

technical name of which is shear thickening fluid (STF), for the =

Ministry of Defence=92s Future Infantry Soldier Technology project.
=93We can=92t yet say STF will stop every bullet, but we are already =

seeing how it provides enhanced protection for less weight,=94 said Eric =

Wetzel, the co-inventor of the substance at the US Army Research =

Laboratory=92s materials centre in Natick, Massachusetts.
A small British company, d3o Lab based in Hove, East Sussex, has =

already developed an STF-based foam that provides extra stiffening =

against impact in commercial products such as goalkeeper gloves, =

snowboarding shoes and ski suits. But the American armour, developed =

in conjunction with the University of Delaware, goes much further.
The silica nanoparticles in STF move around like a liquid under normal =

conditions, but when struck lock together in a solid lattice-like =

structure that lasts only as long as the impact.
A lightweight vest impregnated with STF has already been tested and =

has proved able to stop knife-stabs, fragmentation blasts, lower-power =

bullets and even hypodermic needles. At this level of development, it =

is suitable for staff such as police and prison officers.
The next stage is to strengthen the armour sufficiently to withstand =

high-velocity bullets and shrapnel from roadside bombs.
American and British officials are anxious to improve the =

effectiveness of body armour because of the constant stream of deaths =

and injuries in Iraq and Afghanistan.
Conventional Kevlar body armour with ceramic plate inserts has cut the =

death rate, but is heavy and unwieldy and leaves legs and arms =

vulnerable to severe wounds." =


-- =

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