The fracture of SVM aramide fibers upon a high-velocity transverse impact

Behavior of SVM aramide fibers tested by high-velocity transverse impact with a heavy metal ball incident at a velocity of 670 m/s was experimentally studied using yam with a linear density of 58 tex composed of 300 elementary fibers. The impact interaction was monitored by high-speed photography. The impact leads to fracture of the SVM fibers. According to calculations performed within the framework of a classical theory, no fracture of the fibers should take place. It is suggested that the discrepancy is related to two nonlinear effects. The first is a nonlinear character of the stress-strain relationship at a high level of material deformation, which gives rise to additional tensile strain waves in the fiber with an amplitude different from that predicted by a theory based on linear behavior. The second effect is related to a more complex character of interaction between fiber and ball in the course of impact, whereby the fiber loading is at a least a two-stage rather than a single-stage process. This leads to additional overloading of the fiber, with the resulting stresses exceeding the ultimate tensile strength of the material.