The dynamic response of carbon fiber-filled polymer composites
1 Weapons Experiments Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
2 Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
3 Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
The dynamic (shock) responses of two carbon fiber-filled polymer composites have been quantified using gas gun-driven plate impact experimentation. The first composite is a filament-wound, highly unidirectional carbon fiber-filled epoxy with a high degree of porosity. The second composite is a chopped carbon fiber- and graphite-filled phenolic resin with little-to-no porosity. Hugoniot data are presented for the carbon fiber-epoxy (CE) composite to 18.6 GPa in the through-thickness direction, in which the shock propagates normal to the fibers. The data are best represented by a linear Rankine-Hugoniot fit: Us = 2.87 + 1.17 ×up(ρ0 = 1.536g/cm3). The shock wave structures were found to be highly heterogeneous, both due to the anisotropic nature of the fiber-epoxy microstructure, and the high degree of void volume. Plate impact experiments were also performed on a carbon fiber-filled phenolic (CP) composite to much higher shock input pressures, exceeding the reactants-to-products transition common to polymers. The CP was found to be stiffer than the filament-wound CE in the unreacted Hugoniot regime, and transformed to products near the shock-driven reaction threshold on the principal Hugoniot previously shown for the phenolic binder itself.  On-going research is focused on interrogating the direction-dependent dyanamic response and dynamic failure strength (spall) for the CE composite in the TT and 0∘ (fiber) directions.
© Owned by the authors, published by EDP Sciences, 2012