China successfully developed new superhard material hardness twice the natural diamond
Sherry Huang
www.boreway.net
2015-11-04 15:12:21
Yanshan University professor Tian Yongjun Ma Yanming team and professor of Jilin University, University of Chicago professor Wang Yanbin, in cooperation successfully synthesized under high pressure and temperature hardness twinned diamond twice the bulk of nano natural diamond, which is synthesized by them following the 2013 extremely hard nano-twinned cubic boron nitride after another breakthroughs.
Natural diamond has been recognized as the hardest material in nature, but because of the poor thermal stability, leading to its application is limited in terms of cutting, drilling and the like. After 1955 the US General Electric Company use high temperature and pressure technology synthesized in the laboratory artificial diamond synthesized harder than natural diamond material into the common dream of the scientific community and industry. 2013, Tian Yongjun team first use onion structure under high pressure boron nitride precursor successfully synthesized nano-twinned structure CBN, its hardness exceeds the artificial diamond. The study obtained by the synthetic single crystal diamond in hardness than cubic boron nitride material, breaking the people's material hardening mechanism of traditional understanding, to find a new way to a synthetic high-performance super-hard materials.
So far, through pressure graphite, amorphous carbon, glassy carbon and carbon 60 and other carbon precursor phase transition can not get nano twinned diamond. To this end, Tian Yongjun team and its collaborators began to study the phase transition of carbon onions under high temperature and pressure. At lower temperatures, the formation of carbon nano-onions twinned diamond cubic structure, it is also common to give birth to a monoclinic structure of diamond; diamond nano-twinned structure at higher temperatures, carbon onions turned into a single phase, The average thickness of the twins as small as 5 nanometers. This nano-twinned diamond has never had the hardness and stability. The findings will have broad prospects in the manufacturing of unique properties of new materials.
Natural diamond has been recognized as the hardest material in nature, but because of the poor thermal stability, leading to its application is limited in terms of cutting, drilling and the like. After 1955 the US General Electric Company use high temperature and pressure technology synthesized in the laboratory artificial diamond synthesized harder than natural diamond material into the common dream of the scientific community and industry. 2013, Tian Yongjun team first use onion structure under high pressure boron nitride precursor successfully synthesized nano-twinned structure CBN, its hardness exceeds the artificial diamond. The study obtained by the synthetic single crystal diamond in hardness than cubic boron nitride material, breaking the people's material hardening mechanism of traditional understanding, to find a new way to a synthetic high-performance super-hard materials.
So far, through pressure graphite, amorphous carbon, glassy carbon and carbon 60 and other carbon precursor phase transition can not get nano twinned diamond. To this end, Tian Yongjun team and its collaborators began to study the phase transition of carbon onions under high temperature and pressure. At lower temperatures, the formation of carbon nano-onions twinned diamond cubic structure, it is also common to give birth to a monoclinic structure of diamond; diamond nano-twinned structure at higher temperatures, carbon onions turned into a single phase, The average thickness of the twins as small as 5 nanometers. This nano-twinned diamond has never had the hardness and stability. The findings will have broad prospects in the manufacturing of unique properties of new materials.
