30. Pressure-Shear Plate Impact Experiments on Soda-Lime Glass at Pressures Beyond 20 GPa

Recent modifications of a powder gun facility at Caltech have enabled pressure-shear plate impact (PSPI) experiments in a regime of pressures and strain rates that were previously inaccessible. A novel heterodyne diffracted beam photonic Doppler velocimeter (DPDV) has also been developed for simultaneous measurement of the normal and transverse particle velocity histories using the ±first order diffracted beams produced by a 400 lines/mm diffraction grating deposited onto the polished rear surface of the impacted target plate. We present and interpret the results of PSPI experiments conducted on 5 μm thick soda-lime glass samples subjected to normal stresses beyond 20 GPa and shear strain rates approaching 10⁸ s⁻¹. Transverse particle velocity measurements are used to infer the shearing resistance of soda-lime glass under these extreme conditions.