Mechanics of polycarbonate during high-rate tension

Abstract

Polymeric materials often undergo large inhomogeneous deformations at high rates during their use in various impact-resistant energy-absorbing applications. For better design of such structures, a comprehensive understanding of high-rate deformation under various loading modes is essential. In this study, the behavior of polycarbonate was studied during tensile loading at high strain rates, using a split-collar type split Hopkinson tension bar (SHTB). The effects of varying strain rate, overall impesed strain magnitude and specimen geometry on the mechanical response were examined. The chronological progression of deformation was captured with a high-speed rotating mirror CCD camera. The deformation mechanics were further studied via finite element simulations using the ABAQUS/Explicit code together with a recently developed constitutive model for high-rate behavior of glassy polymers. The mechanisms governing the phenomena of large inhomogeneous elongation, single and double necking, and the effects of material constitutive behavior on the characteristics of tensile deformation are presented.