EFFECT OF NANO SiC ADDITIVE ON MCMB-SiC COMPOSITE FABRICATION VIA MOLTEN SILICON INFILTRATION

C-SiC composites with carbon-based mesocarbon microbeads (MCMB) preforms are new type of highpreformance and high-temperature structural materials for aerospace applications. In this study MCMB-SiC composites with high density (۲.۴۱ g.cm-۳) and high bending strength (۲۱۰ MPa,) was prepared by cold isostatic press of mixed mesophase carbon powder derived from mesophase pitch with different amount (۰, ۲.۵, ۵%) nano SiC particles. All samples were carbonized under graphite bed until ۱۰۰۰ °C and finally liquid silicon infiltration (LSI). Microstructure observations resultant samples were performed by scanning electron microscopy and transition electron microscopy (SEM & TEM). Density, porosity and bending strength of final samples were also measured and calculated. Results indicates that the density of samples with nano additive increased significantly in compare to the free nano additives samples.

Keywords:

Nano SiC , Composite , Liquid Silicon Infiltration (LSI) , Mesocarbon Microbeads (MCMB).