1. College of Metallurgy and Energy， Hebei Polytechnic University， Tangshan 063009, Hebei, China; 2. School of Materials and Metallurgy, Northeastern University, Shenyang 110004, Liaoning, China
Abstract：SiCY3Al5O12(YAG)composite ceramics were prepared by pressureless sintering using SiC powder synthesized from iron ore tailings added with Y2O3 and Al2O3 powders. The phase composition and microstructure were determined by Xray diffraction and scanning electron microscopy. The densification process of sinter is analyzed, and structure and mechanical properties were studied. The results show that the main phase of sinter was SiC, others are YAG and a little FexSiy. The YAG phase formed from Y2O3 and Al2O3 increases and becomes stable with increasing sintering temperature. Fine YAG grains, which disperse around the SiC,grow gradually, bonded shot columnar SiC together playing a role of sintering accelerator. With the increase of sintering temperature, the apparent porosity of sample decreases, while bulk density, hardness and compressive strength increased.
2008, Vol. 43 
