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The deformation of polymers under high loading-rate conditions will be a governing factor to be considered in their impact-resistant applications such as protective shields and armors. In this study, the deformation and fracture behaviors of polymeric materials such as PE, PC and PEEK have been investigated by Taylor cylinder impact tests with the high speed photography. A 20 mm air gun was used to perform the impact experiments. Cylindrical projectiles have been impacted onto a hardened steel anvil at a velocity ranging from 120 to 320 m/s. After impact experiments, the shape of projectiles was examined and compared with high speed photographic images to distinguish the elastic deformation component from the deformation measured instantaneously. Each adopted material showed different deformation and fracture behaviors. As compared with the quasi-static cases all polymers showed a significant strain rate hardening when the strain rate used was over 6 × 10³s⁻¹. This appeared most significant in PE.

In this study we analyzed the deformation of the polymeric rod impacting on the rigid wall which is called "Taylor impact test."" We simulated three-dimensional Taylor impact test depending on the various polymeric materials using the explicit finite element method by employing DYNA3D code. In simulation, polymeric materials were modeled using viscoelastic constitutive relations with the relaxation time and shear modulus. We have carried out the numerical simulation for the transient deformation characteristics and discussed effects of the viscoelastic constants on the deformation of the polymeric rod under impact.

In this paper, an axisymmetric generalized interpolation material point method for fully coupled thermomechanical analysis (AxiCTGIMP) is developed for evaluating the transient responses, where both the thermoelastic and thermoplastic effects are taken into account. The generalized interpolation material point method (GIMP) discretization in space for the coupled governing equations is described in detail. A staggered solution scheme is designed to split the coupled system into the parts related to the temperature and displacement fields, respectively, which are then solved individually with explicit time integration. The AxiCTGIMP is then verified and validated with two benchmark examples: the thick-walled cylinder and the Taylor-bar impact test. The simulation results show good agreements with available analytical solutions, experimental data and other numerical results. In addition, the results indicate that the proposed solution procedure is more accurate than the original MPM while it is much more efficient than the fully three-dimensional simulation for the axisymmetric thermomechanical problems.