The Effect of Filler-Volume Fraction on Crack-Propagation Behavior of Particulate Composites

In the present investigation high-speed photography along with the well-known method of caustics were used for the determination of the crack-propagation velocity and the K _I -stress intensity factor in iron-epoxy particulate composites. Specimens with three different low percentage filler-volume fractions were used; namely, 3%, 5% and 7%. It was found that the mean crack-propagation velocity decreases linearly with increasing filler-volume fraction. In addition, by using the method of caustics, the K _I -stress intensity factor was calculated for each one of the composite specimens separately. It was found that the K _I -S.I.F. increases by steps with increasing crack-length.