A study of surface-coated SiC whiskers on carbon fiber substrates and their properties for diesel particulate filter applications

摘要

β-Silicon carbide (β-SiC) whiskers were synthesized on carbon fiber substrates using a chemical vapor infiltration (CVI) vapor-solid (VS) growth mechanism. An additional SiC surface coating process was utilized after whisker deposition by controlling the input gas ratio of the source gas flow and changing the H_2 (hydrogen) diluent gas to N_2 (nitrogen) under the same deposition temperature of 1,300 °C. As the surface coating deposition time increased, whiskers thickness and spherical blunt tips which were seen at the top edge of the whiskers went thicker. Observing the microstructure of the resulting tips by transmission electron microscopy (TEM) revealed that uncoated whiskers showed few stacking faults, whereas surface-coated whiskers were completely filled with stacking faults.