The Third Hard Materials In The World - Boron Carbide
Posted: May 25, 2017 Clicks: 922
Boron carbide(B4C) is one of the hardest materials in the world, ranking third behind diamond and cubic boron nitride, and it is the hardest material produced in tonnage quantities. Discovered as a byproduct in the production of metal borides during the 19th century, it is produced by reacting carbon with B2O3 in an electric arc furnace through carbo-thermal reduction or gas phase reactions. Boron carbide must be milled and purified to remove metal impurities prior to commercial use.
It has a density of 2.52, a hardness of 2,900-3,580, melts at 2445°C, has a toughness between 2.9 to 3.7, an electrical conductivity of 140, a thermal conductivity of between 30 and 42, thermal expansion of 5, thermal neutron cross section of 600, and a Young’s Modulus of 450 to 470. Its characteristics include:
• Erosion Resistance
• High Hardness
• High Modulus
• Neutron Absorber
The extreme hardness of Boron Carbide (B4C) gives it excellent wear and abrasion resistance and as a consequence it finds application as nozzles for slurry pumping, grit blasting and in water jet cutters.