Materials

Material with new record melting point predicted

Material with new record melti...
Computer simulations predict a combination of hafnium, nitrogen and carbon will have the highest melting point yet
Computer simulations predict a combination of hafnium, nitrogen and carbon will have the highest melting point yet
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A graph of the electron transfer between hafnium and carbon, two of the elements in the suggested new material
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A graph of the electron transfer between hafnium and carbon, two of the elements in the suggested new material
Computer simulations predict a combination of hafnium, nitrogen and carbon will have the highest melting point yet
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Computer simulations predict a combination of hafnium, nitrogen and carbon will have the highest melting point yet

New research predicts it is possible to create a material with a record-setting melting point that would have a good chance of staying intact, even at the insane temperatures in places like the outer edges of Earth's core. Computer simulations run by a team from Brown University find that a precise combination of hafnium, nitrogen and carbon would have a melting point of 4,400 kelvin (7,460° F/4,127° C).

As demonstrated through computer experiments, the material would have a higher melting point than any known substance by at least 200 kelvins and could possibly even stay intact in the coolest layers of the sun (although it would have to somehow get through the blazing hot outer corona first).

The current record belongs to a material made of a combination of hafnium, tantalum and carbon (Hf-Ta-C), but the new simulations predict that just the right amounts of hafnium, nitrogen, and carbon (HfN0.38C0.51) could withstand even more heat. Researchers are currently working to synthesize the substance so that they can test it in a lab.

Nitrogen and carbon are, of course, quite abundant elements, but the lesser known hafnium is used in control rods in nuclear reactors, in vacuum tubes and in the creation of alloys based on metals such as iron and titanium.

A graph of the electron transfer between hafnium and carbon, two of the elements in the suggested new material
A graph of the electron transfer between hafnium and carbon, two of the elements in the suggested new material

It's not clear if the new material itself will actually be useful, even if it does hold up as well as expected when exposed to extreme heat.

"Melting point isn’t the only property that’s important (in material applications)," says Axel van de Walle, associate professor of engineering at Brown and co-author of a paper on the research. "You would need to consider things like mechanical properties and oxidation resistance and all sorts of other properties. So taking those things into account you may want to mix other things with this that might lower the melting point. But since you’re already starting so high, you have more leeway to adjust other properties."

Ultimately, he says the work could help inform the development of materials for use in gas turbines or heat shields on high-speed aircraft, among other possibilities.

Brown's paper was recently published in the journal Physical Review B.

Source: Brown University

5 comments
Dave Ussery
Manned spacecraft should have this material as outer skin for re-entry
MartynWinters
...the creation of metal alloys like iron and titanium... really?
andrewk77
Dave, for that you need good heat insulation properties, not just a high melting point. It didn't mention anything about how good an heat insulator or heat conductor it was.
alcalde
I'm thinking here's some potential for probes to Mercury and Venus that won't melt!
Douglas Bennett Rogers
The corona isn't much of a problem, as it is a low density plasma.