Conventional bullet resistant panels are made by stacking layers of woven Kevlar fabric, saturating these in resin, then pressing and baking them into a single hard sheet. The end result is a 1/4- or 1/2-inch thick sheet of fiberglass with dimensions similar to existing building supplies. While Kevlar-based bullet resistant fiberglass panels are a mainstay of bullet resistant construction, laminators and chemists continue to explore novel solutions to the challenges posed by new weapons in an evolving battlefield.
HYBRID BULLET RESISTANT FIBERGLASS PANELS
Companies like Norplex-Micarta have taken bullet resistant fiberglass one step further with their ShotBlocker composite material. This complex composite is made by laminating together interleaved layers of steel, aluminum, titanium, Kevlar, or ceramics. In this way they can customize the blast protection, spalling, structural, and safety characteristics of their bullet resistant fiberglass. For example, Norplex-Micarta ShotBlocker is the only commercially available fire and smoke-rated ballistic building material, and will neither catch fire nor give off toxic fumes in a blaze..
Individual sheets of these hybrid composites can range from just a fraction of an inch to 8 inches thick, and can be customized for unique applications. Such advanced, multi-material laminates are especially attractive in military applications, where weight, customization, and blast-protection all must be balanced in an effective design.
ONE STEP BEYOND FIBERGLASS BULLET RESISTANT PANELS
In order to craft these custom composites, Norplex-Micarta follows a procedure similar to that used for traditional Kevlar-based bullet resistant fiberglass: the reinforcing materials (be they metal, ceramic, Kevlar, or any combination of other materials) are carefully layered, then saturated with resin. This saturated sandwich is then partially cured, resulting in a still-flexible material. At this stage, the intermediate material (called “pre-preg”) can be immediately sent on to the autoclaves to be pressed and baked into the final product, just like traditional fiberglass bullet resistant panels. Alternately, Norplex-Micarta can ship this flexible hybrid pre-preg directly to customers or third parties, who can mold it into any number of custom shapes to suit their applications. Although many pre-pregs *can be* finished using relatively common tools (most pre-preg needs to be vacuum sealed, and is then cured by baking it for several hours at 300-degrees Fahrenheit) optimal results call for specialized equipment. In other words, don’t plan on making yourself a titanium-carbon-Kevlar battle suit in the garage over a long weekend.
