Preparation of MoSi_2/SiC composite by mechanical-assistant combustion synthesis method

摘要

SiC reinforced MoSi_2 composite powder with nanostructure has been successfully synthesized by mechanical-assistant combustion synthesis method. This process includes a ball-milling process followed by combustion synthesis. The composition and microstructure of as-milled powder mixture were detected by XRD and SEM analysis. Results showed that Mo and Si nanocrystallites could be obtained during the ball-milling process. Compared with normal powder mixture (Mo+Si + C), it could be easily ignited and higher maximum combustion temperature was achieved. Based on XRD and SEM, it was confirmed that MoSi_2/SiC composite powder with nanometric structure could be prepared through combustion method from the mechanical activated powder mixture. At last, the as-synthesized powder was pressureless sintered. The relative density, flexurai strength, Vicker's hardness and fracture toughness of the sintered samples are up to 99 percent , 468.7 MPa, 15.5 GPa and 9.35 MPa m~(1/2)2, respectively.