In-situ Synthesis of ZrN(ZrO_2)/Si_2N_2O Composite Materials from Zircon by Carbothermal Reduction-nitridation Process

摘要

ZrN(ZrO_2)/Si_2N_2O composite materials were synthesized by in-situ carbothermal reduction-nitridation process, with zircon and carbon black as raw materials. The influences of heating temperature and carbon content on synthesis process were investigated, the phase composition and microstructure of the synthesized materials were characterized by X-ray diffraction and scanning electronic microscope. It was found that the decomposition of ZrSiO_4 as well as the formation of ZrN and Si_2N_2O could be promoted by increasing heating temperature and carbon content. ZrN(ZrO_2)/Si_2N_2O composite materials could be synthesized at 1480°C for 6h by heating the sample with ZrSiO_4/C mass ratio of 100/40. The ZrN and Si_2N_2O in the synthesized materials existed in particle shape with an average grain size of about 1-2μm.