Research of dispersion uniformity of carbon fiber in short carbon fiber reinforced silicon carbide composites

摘要

Dispersion of short carbon fibers in silicon carbide (SiC) matrix directly influences the homogeneity of mechanical properties of short carbon fiber reinforced silicon carbide composites, which is always a aporia in fabrication of short carbon fiber reinforced SiC composites, as well as the concentration for investigators in and abroad. in this paper, methyl cellulose (MC), carboxymethyl cellulose sodium(CMC) and hydroxyethyl cellulose (HEC) are respectively used as dispersant, worked carbon fibers are dispersed to unifilar by ultrasonic with addition of the dispersant. Then Ball milling the silicon carbide matrix and the dispersed fibers under the predefined formular to realize the homogeneous mix of the two substances. The paper mainly studies about effects of dispersants, ball milling time and concentration of short carbon fibers on dispersivity of carbon fibers among silicon carbide matrix, and the dispersion of fibers among the matrix was characterized by scanning electron microscope (SEM). The results show that the best dispersion appears when the content of fiber is 10vol% and with HEC as the dispersant, ball milling of 48h.