Preparation of graphene nanoplatelets reinforced SiC composites by oscillatory pressure sintering

Preparation of SiC-based composites with higher relative density and mechanical properties remains challenging. Herein, we report the fabrication of a category of high performance SiC-based composites using oscillatory pressure assisted sintering (OPS) and 0.5 wt% graphene nanoplatelets (GNPs) as reinforced agents. As the sintering temperature changed from 1860 to 1950 degrees C, the relative density and mean grain size of the composites increased from 98.79% to 99.95% and 1.02 mu m to 1.98 mu m, respectively. The SiC-GNPs composites fabricated by OPS possessed much better mechanical properties in comparison with some published data obtained by other sintering methods. The optimal OPS-prepared temperature of the composites was 1920 degrees C; correspondingly, the relative density, flexural strength, hardness and fracture toughness were 99.72%, 488 MPa, 28.94 GPa and 6.73 MPam1/2, respectively. The crucial toughening mechanisms of crack deflection, crack branching, crack bridging and GNPs bridging were also confirmed.

Automated summary

This study successfully fabricated high performance SiC-based composites using oscillatory pressure assisted sintering (OPS) and 0.5 wt% graphene nanoplatelets (GNPs) as reinforced agents. The relative density and mean grain size of the composites increased as the sintering temperature increased. The SiC-GNPs composites fabricated by OPS showed improved mechanical properties compared to data obtained by other sintering methods. The crucial toughening mechanisms of crack deflection, crack branching, crack bridging, and GNPs bridging were also confirmed.