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 imposed
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.
Keywords
dynamic tension, Hopkinson bar, polycarbonate, multiple
necking, finite element modeling, ABAQUS
