Boron carbide (chemical formula approximately B 4 C) is an extremely hard boron – carbon ceramic, a covalent material used in tank armor, bulletproof vests, engine sabotage powders, [2] as well as numerous industrial applications. With a Vickers hardness of >30 GPa, it is one of the hardest known materials, behind cubic boron nitride and diamond.

2019年8月15日 · Boron carbide submicron powder was synthesized with boron oxide and graphene as starting materials by gas-solid reaction method using two different apparatuses. The effects of calcination temperature and holding time, apparatus type and B 2 O 3 /C ratio of the starting materials on the phase composition and morphology of the synthesized powders ...

The only report on the solubility of hydrogen in boron carbide is that by Shirasu et al.206 They exposed crystals of boron carbide to hydrogen gas at various temperatures and pressures for 20 h, and subsequently outgassed them during anneals in which the temperature was linearly increased at the rate of 20 K min −1 up to 1273 K.

1990年1月1日 · Boron carbide, which has a high melting point, outstanding hardness, good mechanical properties, low specific weight, great resistance to chemical agents and high neutron absorption cross-section (10 B x C, x>4) is currently used in high-technology industries—fast-breeders, lightweight armors and high-temperature thermoelectric conversion.

Sub-micron boron carbide powders were synthesized through a gas-solid reaction process using ZIF-8-derived nanoporous carbon and boron oxide as raw materials.

By employing rapid carbothermal reduction it is possible to synthesize highly pure submicron boron carbide with little to no detectable free carbon. Using pressure assisted sintering, RCR powders can be densified to 100% theoretical densities at 1900°C with short hold times.

2009年2月2日 · In the proposed mechanism dichloroborane is formed in the gas phase only as a by-product. Boron carbide, on the other hand, is formed through a series of surface reactions involving adsorbed boron trichloride, adsorbed methane and gas phase hydrogen.

2019年12月4日 · We present the results of investigation of the production of boron carbide by the method of hydrogen reduction of boron trichloride BCl 3 in a vapor of toluene C 7 H 8. The thermodynamics and kinetic features of the deposition of boron carbides in the BCl 3 –C 7 H 8 –H 2 system are investigated.

2023年3月27日 · Herein, by means of the density functional theory study of nanosized boron carbide, we studied the mechanisms of ODH of propane (ODHP) catalyzed by three types of boron carbides, B 13 C 2, B 4 C, and h-BC, which differ from each other in their B contents and their chemical topologies.

2023年1月9日 · Boron combustion in an atmosphere of carbon dioxide can be useful for developing new methods for the synthesis of boron carbide, which is widely used for the manufacture of grinding and abrasive materials, chemical glassware, and protective plates for bulletproof vests, in electronics and the nuclear industry (boron carbide enriched with the 10 ...