Mechanical behavior of nanorubber reinforced epoxy over a wide strain rate loading
Yinggang Miao, Jianping Yin, Wenxuan Du, Lianyang Chen
Abstract
Nanorubber/epoxy composites containing 0, 2, 6 and 10 wt% nanorubber are subjected to uniaxial compression over a wide range of strain rate from 8 × 10−4 s−1 to ∼2 × 104 s−1. Unexpectedly, their strain rate sensitivity and strain hardening index increase with increasing nanorubber content. Potential mechanisms are proposed based on numerical simulations using a unit cell model. An increase in the strain rate sensitivity with increasing nanorubber content results from the fact that the nanorubber becomes less incompressible at high strain, generating a higher hydro-static pressure. Adiabatic shear localization starts to occur in the epoxy under a strain rate of 22,000 s−1 when the strain exceeds 0.35. The presence of nanorubber in the epoxy reduces adiabatic shear localization by preventing it from propagating.