How Bulletproof glass works?

Shattering the science behind what makes the breakable unbreakable

Bullet-resistant glass works by absorbing a bullet’s kinetic (movement) energy and dissipating it across a larger area. Multiple layers of toughened glass are reinforced with alternated layers of polycarbonate – a tough but ﬂ exible transparent plastic which retains the see-through properties of glass. As a bullet strikes the ﬁ rst glass layer, the polycarbonate layer behind it forces the glass to shatter internally rather than outwards.

This process absorbs some of the bullet’s kinetic energy. The high velocity impact also ﬂ attens the bullet’s head. Imagine trying to pierce through a sheet of cotton with the top end of a pencil. It would be very difﬁ cult compared to using the sharp pointed end. The same principle applies here. The ﬂ at-headed bullet struggles to penetrate the layer of polycarbonate. As the bullet travels through each layer of glass and polycarbonate, the process is repeated until it no longer has the speed and shape to exit the ﬁnal layer.

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