Lonsdaleite - the hardest material known to man

[Ender]

link

Diamond will always be a girl's best friend, but it may soon lose favour with industrial drillers.

The gemstone lost its title of the "world's hardest material" some time ago, to man-made nanomaterials of slightly greater toughness. Now a rare natural substance looks likely to leave them all far behind – at 58% harder than diamond.

Zicheng Pan at Shanghai Jiao Tong University and colleagues simulated how atoms in two substances believed to have promise as very hard materials would respond to the stress of a finely tipped probe pushing down on them.

Extreme conditions

The first, wurtzite boron nitride has a similar structure to diamond, but is made up of different atoms.

The second, the mineral lonsdaleite, or hexagonal diamond is made from carbon atoms just like diamond, but they are arranged in a different shape.

The simulation showed that wurtzide boron nitride would withstand 18% more stress than diamond, and lonsdaleite 58% more. If the results are confirmed with physical experiments, both materials would be far harder than any substance ever measured.

Doing those tests won't be easy, though. Because both are rare in nature, a way is needed to make enough of either of them to test the prediction.

Rare mineral lonsdaleite is sometimes formed when meteorites containing graphite hit Earth, while wurtzite boron nitride is formed during volcanic eruptions that produce very high temperatures and pressures.

Flexible friend

If confirmed, however, wurtzite boron nitride may turn out most useful of the two, because it is stable in oxygen at higher temperatures than diamond. This makes it ideal to place on the tips of cutting and drilling tools operating at high temperatures, or as corrosion resistant films – on the surface of a space vehicle, for example.

Paradoxically, wurtzite boron nitride's hardness appears to come from the flexibility of the bonds between the atoms that make it up. When the material is stressed some bonds re-orientate themselves by about 90º to relieve the tension.

Although diamond undergoes a similar process, something about the structure of wurtzite boron nitride makes it nearly 80% stronger after the process takes place, says study co-author Changfeng Chen at the University of Nevada, Las Vegas, an ability diamond does not have.

Single crystals

Natalia Dubrovinskaia from the University of Heidelberg in Germany, has carried out similar research.

"This is important because any attempt to give an insight into the mechanism that improves a material's property, especially hardness, is technologically extremely significant," she told New Scientist.

The more that is understood about what influences the hardness of materials, the more it will become possible to design hard materials to order, she explains.

However, she points out that in order to prove the theory, single crystals of each material would be needed. So far there are no known ways to isolate or grow such crystals of either material.

Journal reference: Physical Review Letters (DOI: 10.1103/PhysRevLett.102.055503)

Hyperlink to the reference at the site. So this isn't like those "supermetal!" websites that are only good for making golf clubs, there is some actual work to reference on this one.

[Zixinus]

This is extremely lab-level material. I'd really would like to know how does the realistic possibilities of mass-production to make actual working parts.

[Serafina]

Well, thats what several nobel prices in chemistry were given for - adapting lab-level procedures for industrial useage.

[Darth Tanner]

If they can't even get hold of enough of the material to perform a laboratory test with it then I find it highly unlikely that either material has any direct applications in industry.

If they can figure out what process is making the wurzite 80% stronger however it might end up being useful for eventual artificial diamond fabrication if the same process can be applied to diamond.

[Sea Skimmer]

They need a contract from DARPA for body armor to speed along work, free money with no results required.

[Zixinus]

They need a contract from DARPA for body armor to speed along work, free money with no results required.

I have to ask: are you being sarcastic or serious?

[Duckie]

If they can't even get hold of enough of the material to perform a laboratory test with it then I find it highly unlikely that either material has any direct applications in industry.

If they can figure out what process is making the wurzite 80% stronger however it might end up being useful for eventual artificial diamond fabrication if the same process can be applied to diamond.

It's not that they can't get enough, it's that they don't have the ability to grow a single crystal of it. They probably want a big giant single crystal to do tests with to verify the mechanical strengths of the material minus any weird crystal cleavage or breaks in the structure issues, but I'm no expert.

[Beowulf]

They need a contract from DARPA for body armor to speed along work, free money with no results required.

I have to ask: are you being sarcastic or serious?

Any reason why he can't be both?

[Ford Prefect]

While it is not as hard as lonsdaleite, wurtzite boron nitride has a much cooler name.

[salm]

While it is not as hard as lonsdaleite, wurtzite boron nitride has a much cooler name.

Really depends. If lonsdaleite is named after the clothes brand lonsdale because working class tough guys wear that brand then lonsdaleite definately has something cool to it.

[Bellator]

Lonsdale clothes are mainly worn by white supremecist youth gangs over here.

[salm]

Lonsdale clothes are mainly worn by white supremecist youth gangs over here.

The Nazis here like them as well but normal people, too. It´s a boxing brand so naturally the martial image is going to attract this type of moron.

But i guess this is going way off topic, so lets shut up.

[Andrew_Fireborn]

Well, according to wiki... It's dubbed in honour of Kathleen Lonsdale.

A couple google attempts later confirm it on a few different sites, that look to have a little more authority.