Synthesis and characterization of SiC/Si3N4 composites from rice husks

Abstract

SiC-SiN composites have been obtained by carbothermal reduction of rice husk under a nitrogen-argon atmosphere at 1450 °C, which is a lower temperature than those used by other authors. On the other hand, tailoring the argon/nitrogen ratio led to the obtained of SiC-SiN composites across the whole range of compositions. Phosphoric acid treatment permited the synthesis of the composite without a pyrolysis step. The final products were characterized by X-ray diffractometry, IR spectroscopy and scanning electron microscopy.