Ultra Fine Boron Nitride (BN) Powder Synthesis in a Non-transferred Arc Plasma Reactor

摘要

Experiments were performed in a non-transferredarc, thermal plasma flow reactor to investigate the synthesis ofultra fine boron nitride (BN) powder from the reaction system ofboron oxide (B_2O_3), methane (CH_4), ammonia (NH_3) andhydrogen (H_2). Argon (Ar) and nitrogen (N_2) were used asplasma gases. The thermodynamics and kinetics of the synthesisreactions were examined and a chemical reaction mechanism wasproposed. The powders produced under certain operatingconditions had high purity and good conversions. All the productswere extremely fine powders (< 30nm) and were uniform in sizedistribution. The powder products were analyzed by chemical andphysical characterization. The effects of the reaction variables onthe conversions from B_2O_3 to BN and the purity of theproducts were investigated.