Think back to the last time you dropped your smartphone. As it smacked against the floor and landed face down, you cringed, afraid to turn it over and see the cracked screen. But it wasn't cracked, and you were able to breathe again. That's because your phone probably has a Gorilla Glass face from Corning; major brands like Samsung, LG, and HTC all use it. You might even have entertained the thought that it would be cool if your car's windshield were that tough.
You wouldn't be alone in thinking that's cool. Ford and Corning are working together to use Gorilla Glass as the windshield and engine cover in the latest Ford GT. Of course, the engineers working on the project aren't worried that you'll drop your car, but driver and passenger safety is critical. In addition to the obvious safety concerns, Ford engineers leave no bolt unturned when it comes to saving weight as well, and Gorilla Glass saves more than 12 pounds (5.4 kilograms) compared to conventional glass in the GT.
Normal windshields have two panes of glass held together by a bonding thermoplastic layer. The GT's windshield is a hybrid, with a glass layer on the outside and a Gorilla Glass layer on the inside, and a noise-reducing thermoplastic sandwiched in between to hold it all together. This makes it far thinner and lighter, yet tougher.
Eric Birbuze, who works with automotive glazing technologies at Corning, told us in a phone interview his team tested the new windshield, and it can withstand Texas-size hail falling at velocities up to 72 miles per hour (115.9 kilometers per hour). "Gorilla Glass has much better impact resistance at high velocities, though it's lighter," he says.
It's also a lot stronger. "Gorilla Glass has an element that makes it unique and tougher — ion exchange," says Birbuze. This chemical strengthening process means that a pane of Gorilla Glass 1-millimeter (.039-inch) thick is five times tougher than a pane of regular automotive glass the same thickness. But here's an interesting fact: As Gorilla Glass gets thinner, it only gets stronger: A pane just half a millimeter (.019-inch) thick is 10 times as strong as regular automotive glass of the same thickness.
"The funny part is that Gorilla Glass can be so strong that we ended up having to tone down the strength," says Michael Musleh, a Ford engineer who worked on the GT. "Requirements are to have the glass to be a bit more pliable, not as hard as people think it should be. The formulation of Gorilla Glass for the GT allows us to soften it up just enough. You want it to be strong enough to nearly eliminate cracks yet be acceptable in a head-on impact."
The thinner, lighter glass also reduces distortion when drivers look through the windshield, improves fuel economy and stops cracks when a rock hits it. Corning expects the glass to result in a 50 percent reduction in windshield repair and replacement claims. And maybe best of all: a thinner windshield defrosts faster, too.