Builders may often hear these types of questions from perspective homebuyers: Why can’t I have another window on this side of the home? Do I really need those obtrusive-looking shutters on the front of my house? Whether its shear capacity that limits openings in seismic regions or concerns over wind-borne debris in hurricanes, the future of glazing may yield more positive answers to these types of questions.
Transparent ceramics are being developed by the Army Research Laboratory (ARL) for armor applications. The materials exhibit enhanced thermal and mechanical properties while maintaining clear vision. The Army envisions a wide range of end use applications to include face shields, windshields, and windows.
Source: U.S. Army Research Laboratory
Ceramics typically are opaque because their trapped pore structure scatters light. Transparent ceramics are manufactured with minimum porosity resulting in transmission of clear images. However, current materials of this type are prohibitively expensive using today’s production methods. ARL is investigating development of low-cost transparent ceramic-based materials to replace current soda/lime/silica glass processes and polycarbonate materials. ARL estimates more-advanced single-chrystal and polychrystalline materials will reduce weight of transparent ceramic materials by 30% and thickness by 40%.
ARL’s goal is improved protection of soldiers. Thus, the focus is on uses in ground vehicles, soldier protection equipment, and other armor systems that require transparency. However, there are numerous commercial applications for this technology including for glazing in the housing market.
Current Status of Technology
Transparent armors have been used on a limited basis in military as well as civilian applications (e.g., law enforcement). Their high cost has limited their use. ARL’s program to develop low cost transparent ceramics is still in the R&D stage. They have developed proto-types to date, including a plated sapphire-based transparent armor material shown in the photograph above.
U.S. Army Research Laboratory
Weapons and Materials Research Directorate
Aberdeen Proving Ground, MD 21005