Glass has a lot going for it: it's easy to clean and you can see straight through it. The only problem is that it's fragile and brittle, and that means it breaks easily. That's why researchers have created a new type of glass that is stronger and tougher than steel.
In fact, this new type of damage-tolerant glass has actually demonstrated a durability greater than any known material.
The new metallic glass is a microalloy that features palladium, a metal with a high "bulk-to-shear" stiffness ratio that counteracts the intrinsic brittleness of glassy materials.
An initially sharp impact does not develop into a fully opened crack. (Image courtesy Robert Ritchie and Marios Demetriou)Those findings come from experiments conducted at the U.S. Department of Energy's Lawrence Berkeley National Laboratory and the California Institute of Technology.
Robert Richie is the materials scientist who led the Berkely contribution to the research. In a press release, he says the new glass is stronger than steel because "that glass undergoes extensive plasticity in response to stress, allowing it to bend rather than crack."
The first samples of this new metallic glass were relatively small glass rods just a millimeter in diameter. When Cal Tech researchers added silver to the microalloy mix, they were able to expand the thickness of the glass rods to six millimeters. This metallic glass needs to be rapidly cooled for the final structure, which limits how large the samples can be.
Researchers believe this work will continue to yield even more durable types of glass. According to Ritchie, "These results mark the first use of a new strategy for metallic glass fabrication and we believe we can use it to make glass that will be even stronger and more tough."
By David Teeghman
