Pressureless Sintering the Al_2O_3/SiC Nanocomposites in Deoxidized Atmosphere

摘要

Many significant improvements have been shown in mechanical properties of ceramic nanocom-posites with ceramic matrix being dispersed with second sub-micro sized (or nano-sized) phase. This study designed and fabricated Al_2O_3/SiC nanocomposites with a raw material used for 85% alumina as matrix and SiC grits in submicro-scale as dispersion phase via a controlled pressureless sintering in air. With coarse SiC powder as bed powder, both C and SiC powder making deoxidized atmosphere, 85 Al_2O_3/SiC nanocomposites with different SiC contents were densified by pressureless sintering at low temperature. Fracture surface investigation indicated that dense nanocomposites with small grain size were produced. General material properties and microstructure were measured and characterized. The results showed that composites sintered in deoxidized atmosphere had better mechanical properties than those sintered in flowing argon.