Who here remembers Star Trek IV: The Voyage Home?
In 1986, a new Star Trek movie was released. And true to the legacy of the film this sequel proved to “predict” a technology that is to come to the future. In this film, Dr. Nichols acquired the formula for “transparent aluminum”. One -inch of this material was said to withstand the pressure exerted by 18,000 cubic feet of water when it would need six-inches of plexiglass for the same amount of pressure. This transparent aluminum was said to be made out of hydrogen, accurentum, and aluminum.
Of course, that is fiction ... until it wasn't.
At around the same time, transparent aluminum was being publicized. But instead of the being made up of the three components in the film's script, the real-world transparent aluminum was made up of aluminum oxynitride. This was nicknamed “AlON”. Creative, right?
The real-life transparent aluminum is classified as a ceramic rather than a metal. A 1.6-inch thick AlON could resist a .50 caliber bullet that would easily pass through bullet-resistant glass twice that thick. It has almost the same strength and hardness as sapphire, with less cost. It is an amorphous solid that allows it to become transparent when polished. It could even allow infrared wavelengths to pass through, something regular glass can't do.
Transparent Aluminum is manufactured by sintering. Fine powders of aluminum oxynitride are packed into a rubber mold. Usually, these molds are in the shape of a half sphere. A process called isostatic pressing binds the powders together by compressing at 15,000 psi. Then, the compressed form, called a green body, is heated at 2000 degrees Celsius for several days. This further fuses the powders together. The resulting product is a strong, cloudy solid that is polished to become transparent.
Projected uses of transparent aluminum are bullet-proof window panes for armored trucks and armor. The ability of transparent aluminum to allow infrared light to pass through is indicative that it may be used for target-seeking missiles. We may find transparent aluminum as smartphone screens one day.
And hey, Star Trek fans wouldn't discount using transparent aluminum in aquariums to transfer humpback whales to the future. All for the sake if humanity.