Stress-strain relationships in yarns subjected to rapid impact loading: 4. Transverse impact tests

Abstract

If a textile yarn segment clamped at each end, is impacted transversely at the midpoint, the stress-strain curve for this yarn can be obtained from measurements on a high speed photographic record of the motion of the yarn. This paper describes the apparatus and procedure used. Stress-strain curves for high rates of straining, on the order of 5,000 percent per second, obtained by this method are given for high-tenacity nylon, Fortisan, and Fiberglas. Comparison with stress-strain data obtained at conventional rates shows that these materials have higher initial moduli, and that their stress-strain curves remain linear up to higher stress values when the testing rate is high. The breaking tenacities are slightly greater and breaking elongation slightly smaller at these high test rates.