Study of the effect of interface properties on the dynamic behavior of Al/PTFE composites using experiment and 3D meso-scale modelling

The compressive responses of aluminium/Polytetrafluoroethylene (Al/PTFE) composite under dynamic loading have been investigated with experiments and simulation, the effect of interface property between the Al granule and the PTFE matrix on the composite’s strength has been studied qualitatively. The dynamic responses at the strain rate of 500 s−1, 1700 s−1, 4000 s−1 were tested on a split-Hopkinson pressure bar (SHPB). A 3D meso-scale model based on micro- CT images was set up to obtain further insight into the deformation of the composite. It was found that the simulated axial stresses were higher than the ones determined by experiments when the nodes along the interface are tied. On the other hand, the results matched very well when the nodes on both sides of the interface are allowed to move against each other. This implies that there the adhesive interaction is relatively weaker and reinforce the interface strength will enhance the strength of Al/PTFE composite. Further research demonstrates that the strength of the interface layer plays a key role in the plastic strain localization and the generation of hot-spots, which arouse the ignition of those composites.