Bulk Modulus of Silicon Carbide Nanowires and Nanosize Grains
R.M. Rich, S. Stelmakh, J. Patyk, M. Wieligor, T.W. Zerda
Texas Christian University, US
Keywords: nanowire, XRD, bulk modulus, SiC, Diamond Anvil Cell
Abstract:Silicon carbide nanowires of average diameter of 30 nm and narrow size distribution were sintered from carbon nanotubes and silicon at 1200oC. X-ray diffraction measurements of those SiC nanowires were conducted in a diamond anvil cell at room temperature and pressures up to 60 GPa. For comparison purposes, we also studied high pressure x-ray diffraction of SiC grains of average sizes of 20 nm, 50 nm, and 130 nm in diameter. The bulk modulus found from these studies depended on the grain size and was 260 GPa for the 20 nm grains, 241 GPa for the 30 nm nanowires, 198 GPa for the 50 nm, and 193 GPa for the 130 nm grains. The reduced compressibility is explained in terms of the core-shell model.