Production of boron carbide and its characterization

Boron minerals have been used during the whole human life history. Nowadays, when contemporary implementations were overviewed which scientific and technologic developments have leaded; it is seen that boron is used in more than 250 materials, 200 of which are without alternatives. Therefore, implementations and activities that use boron mineral as an input source has become a techno-economic issue which interests various numbers of sectors and technologic fields. The carried out study is essential since boron which is the main material of boron carbide constitutes the 72% of the world reserves in Turkey, the value added amount of refined boron is high and the presence of our country in the world?s technologic development.In this study the production of boron carbide and characterization of it is done. High hardness, resistance against many chemical reactions and low density are important properties of boron carbide. Boron carbide is effective and economical due to the fact that it involves approximately 80 % Boron, the melting point of its component is high, chemical and physical stabilities are well for the absorption neutrons. Boron carbide is used in various sectors such as armour plates in army vehicles, space crafts, chemical corrosive areas, in nuclear industry.In industry, boron carbide production is provided by the reaction in 2600 °C carbon resistance ovens or with anhydrous boric acid, graphite or coke dust?s together melting in arc oven. In this study two different raw materials were used for the production of boron carbide precursor. Firstly, production of boron carbide precursor was planned via the mid-product from polyvinyl alcohol and boric acid obtained by sol-gel method was pyrolyzed in 750oC nitrogen atmosphere. In experimental study, initially in order to analyze PVA containing boron?s thermal destruction process during the transformation from polymer to ceramic TGA and DSC analyses were carried out at the heating rates of 3oC/min, 5oC/min, 20oC/min. In order to investigate the effectiveness of waiting temperatures and durations during pyrolyze; XRD, FTIR analyses of the last ceramic product were done. It was observed that the products which are in N2 atmosphere, 3oC/min heating temperature, at 750oC, 3 hours are convenient for the production of boron carbide. Besides citric acid and boric acid was also used for production of boron carbide. The obtained samples? TGA-DSC analysis were done at the heating rate of 3oC/min, 5oC/min, 10oC/min, 20oC/min, besides XRD analysis were done. Boron carbide is produced by heating 2 hours at 1400oC.