Large scale fabrication of dumbbell-shaped biomimetic SiC/SiO2 fibers

The mechanical properties of dumbbell-shaped fiber-reinforced composites are expected to be improved via enhancing the interface adhesion between the matrix and the fibers from the viewpoint of biomimetics. In the present work, the mass production of dumbbell-shaped biomimetic SiC/SiO2 fibers via a facile carbothermal reduction method using gangue and carbon black as raw materials at 1500 degrees C in argon is reported. The phase and morphology of the obtained fibers were characterized using XRD, XPS, FTIR, FESEM and HRTEM techniques. It is found that the string of the synthesized biomimetic fibers is single-crystal 3C-SiC with a diameter of 0.5-1 mu m and the beads are amorphous SiO2 with a diameter of about 5 mu m. The effect of holding time at 1300 degrees C on the morphology is further investigated. Based on these, the growth mechanism of dumbbell-shaped biomimetic SiC/SiO2 fibers is proposed.