文摘
MoSi2 based materials are considered as a potential high temperature structural parts. In this work, a 0.5 wt % Y2O3-20 vol % SiC/MoSi2 composite was successfully prepared by pressureless sintering from mechanical-assistant combustion synthesized powders. Adding a small amount of Y2O3 to the SiC/MoSi2 composite decreased the apparent activation energy of sintering by 10.4 % , resulting in a denser composite with finer grains. The relative density, flexural strength, Vickers hardness and fracture toughness of 0.5 wt % Y2O3-20 vol % SiC/MoSi2 increased by 5.3 % , 27.7 % , 27.2 % and 35.8 % as compared to 20 vol % SiC/MoSi2, respectively. The oxidation mass gain of Y2O3-20 vol % SiC/MoSi2 at 1200 ¡ãC was higher than that of 20 vol % SiC/MoSi2 for 16.9 % , while it still exhibited very good oxidation resistance at this temperature.