..............................................
Bulletproof Glass
How does "bulletproof" glass work?
At
first glance, bullet-resistant glass looks identical to an ordinary pane of
glass, but that's where the similarities end.
An
ordinary piece of glass shatters when struck by a single bullet.
Bullet
resistant glass is designed to withstand one or several rounds of bullets
depending on the thickness of the glass and the weapon being fired at it.
So,
what gives bullet-resistant glass the ability to stop bullets?
Different
manufacturers make different variations of bullet-resistant glass, but it is
basically made by layering a polycarbonate material between pieces of ordinary
glass in a process called lamination.
This
process creates a glass-like material that is thicker than normal glass.
Polycarbonate
is a tough transparent plastic -- often known by the brand name Lexan, Tuffak
or Cyrolon.
Bullet-resistant
glass is between 7 millimeters and 75 millimeters in thickness.
A
bullet fired at a sheet of bullet-resistant glass will pierce the outside layer
of the glass, but the layered polycarbonate-glass material is able to absorb
the bullet's energy and stop it before it exits the final layer.
The
ability of bullet-resistant glass to stop a bullet is determined by the
thickness of the glass.
A
rifle bullet will collide with the glass with a lot more force than a bullet
from a handgun, so a thicker piece of bullet-resistant glass would be needed to
stop a rifle bullet as opposed to a handgun bullet.
There
is also one-way bullet-resistant glass available, which has one side able to
stop bullets, while the other side allows bullets to pass through it
unaffected.
This
gives a person being shot at the ability to shoot back.
This
type of bullet-resistant glass is made by laminating a brittle sheet of material
with a flexible material.
Imagine
a car equipped with this one-way bullet-resistant glass. If a person outside
the car shoots a bullet into the window, the bullet would strike the brittle
side first.
This
brittle material would shatter around the point of impact and absorb some of
the energy over a large area.
The
flexible material then absorbs the remaining energy of the bullet, stopping the
bullet.
A
bullet fired from inside the same car would easily pass through the glass
because the bullet's force is concentrated on a small area, which causes the
material to flex.
This
causes the brittle material to break outwards, allowing the bullet to pierce
the flexible material and strike its target.
No comments:
Post a Comment