Ti-assisted β-SiC nanowhiskers by pyrolysis of PTFE: synthesis and mechanical properties

Abstract

Large quantities of Ti-catalyzed β-SiC nanowhiskers were efficiently prepared via a SHS process by pyrolysis of poly (tetrafluoroethylene) (PTFE). The as-synthesized β-SiC whiskers appear to be structurally uniform with width from 50 nm to 2 μm and length of up to several hundred microns, and they are single crystalline in nature. Results demonstrated that Ti particles could significantly accelerate the absorption and dissolving of Si- and C-related fragments. A Ti–Si–C alloy droplet was detected at the end of an individual β-SiC whisker, which indicated that β-SiC whiskers were grown via the vapor–liquid–solid (VLS) growth mechanism. The elastic bending modulus of individual whiskers was measured by an in-situ transmission electron microscopy (TEM) process; the average value of the elastic bending modulus of individual as-synthesized whiskers was 554 GPa.