Diamonds may be a girl's best friend, but “new diamonds” may be an engineer's.
A new form of highly-compressed carbon may be even stronger than diamonds, since it may be able to withstand extreme pressure from all directions, unlike diamonds which are harder in one orientation than another.
Natural diamonds are created when carbon is subjected to extreme heat and pressure deep within the Earth. A team of Stanford University scientists created the “new diamonds” by compressing glassy carbon to above 400,000 times normal atmospheric pressure.
Carbon, the fourth most abundant element in the universe, can take on many forms, called allotropes. Diamonds and graphite are two familiar allotropes of carbon. Glassy carbon and buckminsterfullerenes are two others. Glassy carbon was first synthesized in the 1950's. It combines the properties of glass and ceramics with those of graphite.
The newly created allotrope, or “new diamond,” can withstand 1.3 million times normal atmospheric pressure in one direction while confined under a pressure of 600,000 times atmospheric levels in other directions. Diamonds are the only other substance which can withstand that kind of pressure.
Diamonds are crystals. The crystalline structure of diamonds means that the rock's hardness depends on its orientation.
Unlike diamonds, the new material is not a crystal. It is an amorphous material, meaning that its structure lacks the repeating atomic order of a diamond crystal. This quality could make the new material superior to diamonds, if it proves to be equally hard in all directions.
"These findings open up possibilities for potential applications, including super hard anvils for high-pressure research and could lead to new classes of ultradense and strong materials," said Russell Hemley, director of Carnegie's Geophysical Laboratory, the laboratory where the “new diamond” was forged, in a press release.
Diamonds (Wikimedia Commons)
Tunneling electron microscope image of glassy carbon (Wikimedia Commons)