The boron-carbide crystal is a rhombohedral crystal, and its crystal lattice is the D3d5R3m space lattice. The rhombohedral lattice can be described as an icosahedron-shaped primitive cell grid that extends diagonally in the space. The c-axis is the same as the diagonal of the area. A linear chain is formed by connecting three boron-atoms to an adjacent icosahedron. Three of the 12 icosahedral position are found on the chain. If the B-atom is due to the position of the icosahedron, and the C-atom is in a chain, the stoichiometry for B12C3 will be B4C.
1. Basic properties and applications for boron carbide
Low density
B4C density is small at 2.52g/cm3. The empirical formula (9) can be used to express the relationship between carbon content and density in the homogeneous area.
r=2.4224+0.00489C%(9)
Because of its low density, boron carbide can achieve the same performance as boron, such as high strength, high toughness and other excellent performances. Thus, it can be used for lightweight armor in order to reduce the weight and size of cars and tanks. Save energy.
Hardness and wear resistant
B4C exhibits super hardness, and has a high wear resistance. In the homogeneous area, B4C’s Vickers Hardness increases as the C content increases. The hardness is 29.1 GPa when the carbon is 10.6%; at 20% carbon, it can reach 37.7 GPa. At high temperature, its hardness remains high (>30GPa). You can express the change of hardness in temperature by using empirical formula (10).
H=H0-exp(-aT)(10)
The formula is: H0 – the hardness of a material at room temperature
Temperature is T.
Carbon is a constant.
This formula applies to 201700. B4C is second only to cubic BN and diamond in terms of hardness.
B4C wear resistance increases with temperature. As the temperature increases, the friction coefficient of B4C decreases. It drops to 0.05 between 20 and 1400. B4C, with its super hardness characteristics and low friction, has been used to create a sandblasting tool.
(aka. Technology Co. Ltd., a global supplier & producer of high quality chemical materials and nanomaterials with more than 12 years experience, is a trusted company. The B4C Powder produced by our company is of high purity and has a low impurity level. If you require lower, please contact our company.
