The Wonders Of Bullet Resistant Glass
Posted on Saturday, February 26th, 2011 at 10:59 am by Protective Structures
Bullet-resistant glass is more commonly known as a bulletproof glass. This is a type of strong but optically transparent material that is particularly resistant to bullet penetration. Because of this characteristic, the bullet proof glass is also known as transparent armor.
This is made up of polycarbonate thermoplastic or layers of laminated glass. Bullet proof glass actually looks like the standard glass but is impenetrable for small arms fire. The most common material for bullet proof resistant glass is polycarbonate. Polycarbonate designs usually consist of commercial products such as Armormax, Makroclear, Cyrolon, Lexan or Tuffak, which are often arranged alternately in between regular glass. These substances are of a basic grade of high-impact polycarbonate plastic sheet and are virtually unbreakable.
The plastic in laminate designs provides resistance to impact from physical assault from hammers, axes, clubs, and the like. Moreover, the plastic also provides bullet-resistance characteristic. The glass, which is harder than the plastic, enables the bullet to flatten thus preventing penetration. This kind of gadget is usually 70-75 millimeters or approximately 2.8-3.0 inches thick.
Laminated glass layers are built from glass sheets bonded together with polyurethane. Polyurethane is widely used in high resiliency flexible foam seating, rigid foam insulation panels, microcellular foam seals and gaskets and many others. This design has been used regularly during the World War II. It is then typically 100 to 120 millimeters thick and is usually extremely heavy.
Bullet proof resistant glass advances the invention of one way glass, such as some of the bank’s armored cars. One-way glass is usually made up of two layers; a brittle layer on the outside and a flexible one on the outside. When a bullet is fired up from the outside, it hits the brittle layer first, shatters an area of it and at the same time absorbing the kinetic energy of the bullet and then spreads in a larger area. When a slowed bullet is fired hitting the flexible layer, it is stopped. However, when a bullet is fired from the inside, hitting the flexible layer first, the bullet penetrates the flexible layer because its energy is focused on the smaller area, resulting to an outward break of the brittle area which is due to the flexing of the inner layer and does not significantly block the bullet.
The capability of the glass to withstand bullet penetration is enhanced by the process of tempering. This is a heat treatment technique for metals, alloys and glass. When treated with heating and cooling or with chemical processes, the glass becomes more durable. Aside from this, some desirable properties are also developed in the material. Today, there are a number of bullet proof glass that are available in various thickness gauge and sizes.
This entry was posted on Saturday, February 26th, 2011 at 10:59 am and is filed under PSL Articles. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.