If you are looking for high-quality products, please feel free to contact us and send an inquiry, email: brad@ihpa.net
Diamonds are a girl’s best friend but wurtzite boron nitride may be about to leave them in the dust. Scientists have used computer simulations to predict that this rare natural substance is 18% tougher than the world’s most famous gemstone.
Boron nitride comes in four different crystalline structures: amorphous, hexagonal (like graphite), cubic and the rare wurtzite form. Cubic boron nitride, which has a Vickers hardness of about 50 GPa, is already the second hardest material after diamond. Its hexagonal form was initially claimed to be even harder, but this claim was based on theoretical simulations rather than experimental testing. This is because wurtzite boron is very rare and difficult to make in substantial amounts.
Zicheng Pan of Shanghai Jiao Tong University in China and his colleagues simulated how atoms in two substances believed to be promising very hard materials would respond to the stress of a finely-tipped probe pushing down on them. Their calculations suggest that wurtzite boron has a tetrahedral structure, which is stronger than the face-centred cubic structure of diamond. This gives it an indentation strength that is 114 GPa, or about 18% harder than diamond.
Lonsdaleite, a variant of wurtzite boron, is 57% more powerful than diamond in this test and can only be found in microscopic quantities within meteorites. This finding could help scientists design materials with the strength and durability they need to withstand extreme conditions, for example in aerospace applications. But the scientists are also keen to use their research to develop a new type of diamond that’s cheaper to produce than the precious gem.