Dynamic and Static Torsional Characterization of Pultruded Hybrid Cylindrical Composite Rods

Abstract

The objective of this paper is to demonstrate the effects of hybridization on the static and dynamic behavior of pultruded composite rods subjected to a torsional mode of deformation. Candidate materials that were tested included cylindrical composites made from unidirectional glass and graphite fibers, and hybrids of glass-graphite/epoxy in various shell-core type configurations, fabricated by the pultrusion manufacturing process. The dynamic torsional stiffness and damping were evaluated by the FFT based impulse-frequency response vibration technique. The static shear modulus was obtained using a conventional low torque tester and the initial tangent modulus method. This study has shown that for a given fiber volume fraction glass/epoxy exhibits higher shear modulus than graphite/epoxy; and hybridization of these two material systems results in better dynamic performance by placing glass fibers in the outer shell region.

Keywords

pultruded composites dynamic shear modulus hybrids impulse-frequency response technique shear loss factor static shear modulus

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