High Strain Rate Behavior of Carbon Nanofiber Reinforced Vinyl Ester
The dynamic uniaxial compressive response of neat vinyl ester resin with and without the addition of a dispersing agent and vinyl ester reinforced with both 0.50 and 1.00 parts (by weight) per hundred (parts of) resin of vapor grown carbon nanofibers was analyzed using a classical split Hopkinson pressure bar at strain rates ranging from 750 s -1 to 2350 s -1. Dynamic force equilibrium was verified at all strain rates in order to validate the small strain data and the observed dynamic elastic modulus. Both the effects of the dispersing agent and the nanofiber loading level conducive for optimal yield stress and stiffness were shown to be highly strain rate dependent. Due to the viscoelastic nature of the vinyl ester resin/matrix, the differences in the observed dynamic stress-strain response (notably yield stress and stiffness) of all four material configurations likely was attributed to the coupled effect of the strain rate and the associated internal temperature rise experienced during split Hopkinson pressure bar tests. Copyright 2009 by Thomas Lacy.
name of conference
50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference