Australian scientists accidentally create one of the most thermally stable materials in the world. Up to 1400 ° C, it does not expand
Researchers at the University of New South Wales (UNSW) in Australia were researching batteries when they accidentally discovered that a composite material they were working with had a phenomenal ability to withstand heat. The composite material did not change in volume at all at temperatures ranging from 4 to 1400 Kelvin (-269 to 1126 ° C, -452 to 2059 ° F). It is perhaps the most thermally stable material in the world.
This wonderful material does not sweat even at temperatures well above the boiling point of some metals.
In elementary physics, we were told that when the temperature of a material increases, its volume also increases. This phenomenon is known as thermal expansion. This thermal expansion or contraction is proportional to the change in temperature and is attenuated by the coefficients of thermal expansion typical of each material. For example, with the same increase in temperature, aluminum expands more than copper, which in turn expands more than gold, which expands more than iron, and so on. In response to temperature, it is normal for the material to also undergo alterations in other properties, such as strength, toughness or elasticity.
However, some materials are thermally stable, which means they can maintain their properties at required temperatures for extended service life. Extended thermal stability at high temperature is particularly desirable in the automotive, marine and aerospace industries.
One of the most promising thermally stable materials in the world was recently reported by a team of researchers led by Professor Neeraj Sharma of the University of New South Wales. Using state-of-the-art instruments such as the Australian synchrotron and Australian Neutron Scattering Center at the Australian Nuclear Science and Technology Organization, researchers have shown that a zero thermal expansion material composed of scandium, aluminum, tungsten and oxygen does not change in volume even when heated to near 1400 ° C.
Write in the journal Materials chemistry, the authors reported only minute changes in the bonds and rotations of the arrangements of atoms in the structure of Sc1.5 Al0.5W3O12 . The material is easily synthesized, and the high availability of alumina and tungsten oxide can enable large-scale fabrication for use in high-precision mechanical instruments, control mechanisms, aerospace components, and medical implants. .
Remarkably, the properties of the composite material were discovered by accident while the researchers were busy with other work.
“We were experimenting with these materials in conjunction with our battery research, for unrelated purposes, and we stumbled upon this singular property of this particular composition,” Sharma said in a statement.
Next, Sharma and her colleagues plan to analyze the individual contribution of each ingredient in the composite material.
“Which part acts at which temperature, well, that’s the next question,” says Sharma, who adds, “scandium is rarer and more expensive, but we are experimenting with other elements that could be substituted, and the stability maintained. “