SiC-Al2O3 powder synthesized by microwave heating carbothermal reduction of fly ash

SiC-Al₂O₃ powders were synthesized by microwave heating carbothermal reduction reaction between fly ash and carbon black. Effects of temperature, carbon content, reaction time and carbon sources on the phase compositions of synthesized powders were studied. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM) and laser particle size analyzer were applied to characterize the products. The results show that carbon content and reaction temperatures are important factors on phase compositions of synthesized powder, the proper temperature for synthetizing SiC-Al₂O₃ powders is 1300°C. SiC-Al₂O₃ Powder, synthesized with excess 5% content of carbon at 1300°C, have a mean particle size of 5.6μm. SEM and TEM graphs show the morphological aspect of SiC Al₂O₃ Powder. SiC particles and SiC whiskers are present, as well as Al₂O₃ plates.