Application of ultrasound for preparation of carbon fiber cement-based composites

In order to improve the dispersion of carbon fibers in cement-based composites,we propose two improved ultrasound-assisted dispersion technologies,in which only carbon fiber or both carbon fiber and a small quantity of silica fume in aqueous solution are sonicated with an ultrasonic generator.Their dispersion efficiency for carbon fiber in cement-based composites is evaluated with the mean value and the variation coefficient of resistivity,and the influence of ultrasound treatment time on the dispersion efficiency is explored.Experimental results indicate that the two improved ultrasound-assisted technologies can enhance the uniformity of carbon fiber in cement-based composites and their dispersion efficiency increases with the increasing ultrasound treatment time before the critical time.