| In this paper, the development on experimental synthesis and theoreticcalculation of boron carbide compounds has been introduced briefly. Thesynthetic methods and characterized methods of boron carbide have also beensummarized. Using boric acid and sucrose as raw materials, a boron carbideprecursor with turbostratic structure has been prepared by a chemicalcombination pyrolysis method. The precursor and the mixture of precursor andcatalyst have been treated under high temperature and high pressure,respectively. The structures, compositions, surface image, bonding propertiesof the precursor and the sample after treatment by high temperature and highpressure have been characterized by XRD, EDS, SEM, TEM and EELS.The experimental results suggest that the precursors were different underdifferent temperatures. The most precursor processed under 1200 ℃ wasB-C compound with turbostratic structure. It contained a little B2O3. The B4Cwould appear in the precursor when it was treated above 1200 ℃. The contentof B4C increased with increasing temperature.Well crystallized graphite-like sample was obtained under temperature of1600 ℃ and pressure of 5.5 GPa treatment using turbostratic B-C precursortreated at 1200 ℃. TEM analysis results showed that polycrystalline B-Ccompound was formed in the sample. EELS analysis results suggested thatsome of the polycrystalline B-C compound was hexagonal crystal and had acomposition close to BC3. Its lattice parameters were a=0.252 nm, c=0.678 nm.Using CaB2C2 as catalyst, graphite-like crystal was acquired under hightemperature of 1600 ℃ and pressure of 5.5 GPa by treating turbostratic B-Cprecursor. TEM analysis results indicated that the sample was composed ofturbostratic structure and polycrystal B-C compound. EELS analysis resultsdemonstrated that the polycrystalline contained lower boron and higher carbon.The highest ratio of boron to carbon in the B-C compounds was 1:7. And itslattice constants were a=0.247 nm, c=0.672 nm.
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