Dynamic mechanical properties of polycrystalline graphites and a 2D-C/C composite by plate impact

In order to obtain dynamic mechanical properties of carbon materials, i.e., two kinds of polycrystalline graphites and a C/C composite. plate impact e xperiments with simultaneous three poly vinylidene difluoride (PVDF) stress gauges were conducted using a one-stage powder gun system. By this measure ment system, Hugoniot curves, rarefaction wave velocities and stress-strain (S-S) curves could be obtained. The Hugoniot curves were valid, rarefactio n wave velocities increased with the plateau stress in the specimen, and th e slope of the S-S curve was consistent with that of the Hugoniot curve. Th ese dynamic mechanical properties of the carbon materials are useful not on ly for the understanding of the dynamic behavior but also for impact fractu re behavior. (C) 2001 Elsevier Science Ltd. All rights reserved.