Nanotechnology may revolutionize future engines
At the US Army Research Laboratory, scientists are on the hunt for nanomaterials that could improve engine technology in a big way.
“What we’re seeing is a revolutionary property arising in a class of materials that we never thought was possible,” said Dr. Kristopher A. Darling, a materials scientist with the laboratory’s Lightweight and Specialty Metals Branch.
Darling and his team of collaborators published new findings which they believe could lead to many new materials applications, including inside turbine engines, where temperatures can soar to more than 2,500 degrees Fahrenheit.
Darling outlines how his team stabilized a copper alloy microstructure and found it to be strong at very high temperatures.
The Department of Defence depends on jet turbine engines that require just this combination of high-structural strength coupled with high thermal stability, though the material is copper, not a material typically used in engines.
But what it demonstrates is that these types of microstructures are capable of achieving properties that are extraordinarily high in comparison to what one would normally see in a conventional type of material.
The team hopes to recreate the combination of properties within other types of materials like nickel, cobalt or tantalum, which would have the potential to revolutionize engine technology.
“We’re seeing orders of magnitude improvements in the creep response,” he said. “There is a six to eight orders of magnitude increase in creep response relative to what conventional nanocrystal materials can do.”
Darling said the findings are all about the “creep response”, which refers to how materials deform under continuous stress at elevated temperatures.
According to Darling, results from the preliminary tests of the material left the scientists scratching their heads. So they reached out to colleagues at the University of North Texas and Arizona State University to confirm what they were observing was correct.
“A lot of times unique discoveries are made by accident or by sheer luck, and this was one of those cases where we started to probe the material and we didn’t see the response that we were expecting,” Darling remembered. Scientists at these institutions were just as baffled.
Nanotechnology research in metals is a relatively young field. Just a couple of decades ago, researchers were just learning how to synthesize nanomaterials in bulk form and just beginning to understand their fundamental properties.
Darling has been studying this material for about five years. He started working at the laboratory after earning his doctoral degree from North Carolina State University in 2009.
The US Army Research Laboratory is part of the US Army Research, Development and Engineering Command, which has the mission to ensure decisive overmatch for unified land operations to empower the Army, the joint warfighter and the nation.