by Brooks Hays
Nagoya, Japan (UPI) Feb 8, 2017
Materials scientists in Japan have discovered a new material that contracts when heated, a rarity.
The metal-ceramic composite material is composed of calcium, ruthenium and oxygen atoms. When heated, it shrinks 6.7 percent. It's a new record for negative thermal expansion, or NTE.
In many modern industries -- whether electronics, aeronautics or medical equipment -- devices and the machinery used to build them must maintain precision and predictability while enduring harsh conditions. Temperature changes can diminish these qualities, cause materials to degrade and deform as they contract and expand.
Because most materials expand upon heating, NTE materials can help industrial engineers more precisely manage cycles of contraction and expansion.
By mixing normal materials with NTE materials, engineers can create new composite materials with a thermal expansion value close to zero.
X-ray images suggest the new material is atomically altered by heat, triggering unique changes to its microstructure and resulting in a loss in volume. Scientists discovered voids surrounding the material's unique arrangement of crystal grains.
"The non-uniform changes in the atomic structure seem to deform the microstructure of the material, which means that the voids collapse and the material shrinks," Koshi Takenaka, a material scientist at Nagoya University in Japan, said in a news release. "This is a new way of achieving negative thermal expansion, and it will allow us to develop new materials to compensate for thermal expansion."
Researchers described the new material in the journal Nature Communications.
Space Technology News - Applications and Research
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|