Low temperature synthesis and characterization of high purity nano boron carbide (B4C) structures

Boron carbide (B4C) is accepted as an important engineering material due to its high melting point, high hardness, high Young's modulus, excellent radiation (neutron) absorption properties and low thermal conductivity. Although different methods, such as high temperature carbothermic reduction and chemical vapor decomposition, have been used to synthesize boron carbide, a low cost technique that provides high purity B4C with no residual carbon, is required by industry. Therefore, in the present study, synthesis of high purity, high crystallinity nanostructured boron carbide particles with various morphologies, is proposed using a modified low-temperature sol gel process. The effects of starting chemicals, calcination and sintering temperature/time on the formation of B4C structures, morphology and stoichiometry were reported. Detail characterization studies including TEM, XRD, NMR and DTA were used to support the results on the formation of stoichiometric boron carbide with high crystallinity at low temperatures.