A number of prominent auto manufacturers in the US are currently considering using “Gorilla Glass” as a means of cutting down total vehicle weight, thereby improving fuel economy, according to recent reports.
The idea is that, since Gorilla Glass is stronger than conventional glass, less would be needed — perhaps reducing material weight by 25–30%, according to the manufacturer, Corning. As conventional car windshields usually weigh around 20 pounds, that would equate to a weight reduction of around 5–7 pounds — of course, if glass other than the windshield was replaced as well, then this reduction could be increased.
According to Corning, every pound of weight reduction would equate to roughly $2–4 in additional costs — not a huge amount, but hey, “every little bit counts.”
A big part of the new interest in the material is owing to the need that auto manufacturers have to improve fuel economy — in order to keep to the requirements of the US Corporate Average Fuel Economy (CAFE) standards, which call for manufacturers to meet a fleet average of 54.5 miles per gallon by 2025.
As a result, Ford and others have been researching the use of the material, and some companies, such as BMW, have begun utilizing it for specific purposes. The beautiful BMW i8 plug-in hybrid (PHEV), for example, utilizes a pane of Gorilla Glass as a barrier between the engine compartment and the cabin of the car.
Green Car Reports provides a bit more information:
Carmakers are cautious in trying new materials for auto glass, because some of the panes are an important element of vehicle safety. Gorilla Glass is made by immersing sheets of glass in a bath of molten salt. In the bath, sodium ions are replaced by potassium ions, creating compression and increasing the durability of the material.
It’s also possible that Gorilla Glass will be used to supplement conventional soda-lime glass, rather than replace it completely. A typical windshield is made from two 2.1-milimeter glass panels laminated together. Corning is proposing using a thinner, 0.7-mm sheet of Gorilla Glass for the inner panel. Something like this was demonstrated on the Ford Fusion Lightweight Concept, which had a windshield made from panels of soda-lime glass and Gorilla Glass.
While Ford has previously tested an all–Gorilla Glass windshield, it was reportedly not thick enough to provide enough soundproofing + stiffness — meaning that such mixed-glass applications seem more likely.