Boron carbide

Jump to: navigation, search
Template:Chembox E numberTemplate:Chembox SolubilityInWater
Boron carbide
IUPAC name Boron carbide
Other names Tetrabor
Black Diamond
ECHA InfoCard Lua error in Module:Wikidata at line 879: attempt to index field 'wikibase' (a nil value). Lua error in Module:Wikidata at line 879: attempt to index field 'wikibase' (a nil value).
Molar mass 55.255 g/mol
Appearance Black powder.
Density 2.52 g/cm3, solid.
Melting point
Boiling point
Crystal structure Rhombohedral
Main hazards Harmful, irritant.
Related compounds
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Boron carbide (chemical formula B4C) is an extremely hard ceramic material used in tank armor, bulletproof vests, and numerous industrial applications. With a hardness of 9.3 on the mohs scale, it is the fifth hardest material known behind boron nitride, diamond, ultrahard fullerite, and aggregated diamond nanorods.

Discovered in the 19th century as a by-product of reactions involving metal borides, it was not until the 1930s that the material was studied scientifically. Boron carbide is now produced industrially by the carbo-thermal reduction of B2O3 (boron oxide) in an electric arc furnace.

Its ability to absorb neutrons without forming long lived radionuclides makes the material attractive as an absorbent for neutron radiation arising in nuclear power plants. Nuclear applications of boron carbide include shielding, control rod and shut down pellets. Within control rods, boron carbide is often powdered, to increase its surface area.


  • Carbide, Nitride and Boride Materials Synthesis and Processing ISBN 0-412-54060-6


External links

de:Borcarbid it:Carburo di boro sv:Borkarbid