Newly Identified Metal Tougher Than it Looks
Updated: Oct 14, 2020
“You can never be too rich,” goes the old axiom, “or too thin.”
Popular science is bearing at least the latter assertion out with the recent development of an infinitesimally thin metal film produced from a new class of metal alloys.
And this smart film is more noteworthy still, given its demonstrated ability to survive very high temperatures and extreme pressures.
Researchers at ETH Zurich, an engineering, science, technology, mathematics, and management university in Switzerland, have milled the remarkable film—made of equal parts niobium, molybdenum, tantalum, and tungsten—into “micropillars” that are a full ten times stronger than a block made of the same high-entropy alloy material.
This impressive quality of ductility means these pillars—which are just three micrometres thick—can be compressed by up to a third of their length under high pressures without becoming brittle or cracking.
Like most high-entropy alloys, this latest discovery offers not only impressively high strength but impressively high corrosion resistance, too. And what’s more, the ETH researchers’ material is distinctive for its ability to resist temperature changes like a champ. Most other metals whose internal structures are made up of the arrangement of elaborate internal crystal structures like this one suffer destructive sensitivity to temperature change.
However, ETH’s wonder film survived three days at 1,100 degrees Celsius with no significant change to either its external or its internal structure.
For more than 4,000 years, humans have been tinkering with metal alloys in a bid to land upon a material that possesses the most desirable combination of properties. That this latest alloy will end the pursuit is unlikely — but it’s irrefutably a (rich, thin) step in the right direction.