Heterodiamond
Encyclopedia
Heterodiamond is a superhard material containing boron
, carbon
, and nitrogen
(BCN). It is formed at high temperatures and high pressures, e.g., by application of an explosive shock wave
to a mixture of diamond
and cubic boron nitride. The heterodiamond is a polycrystalline material coagulated with nano-crystallites and the fine powder is tinged with deep bluish black. The heterodiamond has both the high hardness of diamond and the excellent heat resistance of cubic BN
. These characteristic properties are due to the diamond structure combined with the sp3 σ-bonds among carbon and the hetero atoms.
Cubic BC2N can be synthesized from graphite-like BC2N at pressures above 18 GPa and temperatures higher than 2200 K. The bulk modulus
of c-BC2N is 282 GPa which is one of the highest bulk moduli known for any solid, and is exceeded only by the bulk moduli of diamond and c-BN. The hardness of c-BC2N is higher than that of c-BN single crystals.
Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...
, carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
, and nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
(BCN). It is formed at high temperatures and high pressures, e.g., by application of an explosive shock wave
Shock wave
A shock wave is a type of propagating disturbance. Like an ordinary wave, it carries energy and can propagate through a medium or in some cases in the absence of a material medium, through a field such as the electromagnetic field...
to a mixture of diamond
Diamond
In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions...
and cubic boron nitride. The heterodiamond is a polycrystalline material coagulated with nano-crystallites and the fine powder is tinged with deep bluish black. The heterodiamond has both the high hardness of diamond and the excellent heat resistance of cubic BN
Boron nitride
Boron nitride is a chemical compound with chemical formula BN, consisting of equal numbers of boron and nitrogen atoms. BN is isoelectronic to a similarly structured carbon lattice and thus exists in various crystalline forms...
. These characteristic properties are due to the diamond structure combined with the sp3 σ-bonds among carbon and the hetero atoms.
Cubic BC2N can be synthesized from graphite-like BC2N at pressures above 18 GPa and temperatures higher than 2200 K. The bulk modulus
Bulk modulus
The bulk modulus of a substance measures the substance's resistance to uniform compression. It is defined as the pressure increase needed to decrease the volume by a factor of 1/e...
of c-BC2N is 282 GPa which is one of the highest bulk moduli known for any solid, and is exceeded only by the bulk moduli of diamond and c-BN. The hardness of c-BC2N is higher than that of c-BN single crystals.