Synthesis, characterization and growth mechanism of SiC fibers

The smooth 2H-SiC fibers with hexagonal structure and a small amount of tower-like 3C-SiC fibers with facecentered cubic structure were synthesized with a simple catalyst-free method. Specifically, SiC fibers were obtained by thermal treatment of the Si3N4 powder in a graphite crucible at temperature of 1800 degrees C and pressure of 190 MPa in Ar atmosphere. The synthesized SiC fibers consist of SiC wires with several tens to hundreds of micrometers in length and mostly 200-800 nm in diameter and some SiC whiskers with shorter length of 3-15 mu m. The smooth 2H-SiC fibers and rough 2H-SiC fibers with tower-like growth traces grown along [1010] direction, and the tower-like 3C-SiC fibers may grow with orientation attachment patterns along [111] direction. Finally, the vapor-solid growth mechanism and detailed growth process of SiC fibers were discussed.

Automated summary

Smooth 2H-SiC fibers and a small amount of tower-like 3C-SiC fibers were synthesized successfully using a simple catalyst-free method. The synthesized SiC fibers consist of SiC wires and whiskers, showing different morphologies and growth orientations. The growth mechanism and process of SiC fibers were also discussed.