Dynamic Behavior of the Hybrid Composite Materials Subjected to Tensile Stresses at High Strain Rate

Abstract

This study aims to the design and manufacture of a split Hopkinson tension bar apparatus. The dynamic tensile behavior of hybrid composite materials at high strain rates is investigated. The most important characteristic of split Hopkinson apparatus is a (gun system) responsible of dynamic tension process depending on a spring system in its operation. Two groups of materials were tested at different strain rates; first group is woven fiber glass/ epoxy composite, woven carbon fiber/ epoxy composite and hybrid woven glass/ woven carbon epoxy laminates. The experimental results for the first group showed that the values of maximum stress, specific absorbed energy and kinetic energy increased approximately 12.4 %, 11% and 10% respectively for woven fiber glass/ epoxy composite when it’s hybridized with woven carbon fiber/ epoxy composite. In the second group using woven jute fiber as a natural material which have low cost and is environmental friendly, when these materials are hybridized with glass fibers and carbon fibers resulted in improves of the tensile properties. When woven jute fiber hybridized with glass fibers the value of maximum stress, absorbed energy and kinetic energy increase by approximately 38.33%, 38% and 55 % respectively. On the other hand hybridization of woven jute fibers with woven carbon fibers lead to increase in the values of maximum stress, absorbed energy and kinetic energy approximately 43%, 44% and 68% respectively. Based on experimental results the modulus of elasticity is increased with increasing the strain rates. The first group yielded higher properties than the second group. Also the effect of stacking sequence on tensile test has been investigated experimentally. Static tensile test carried out for comparison of dynamic test results and assessment of these results analytically by using Johnson-Cook constitutive model.