Development of a diagnostic based on ruby luminescence for pressure measurement during dynamic loading experiments on high-pulsed power drivers

The CEA Gramat dedicates a significant part of its activities to study the dynamic behavior of various materials of interest. Dynamic loading experiments, mainly quasi-isentropic compression experiments, are achieved on several High-Pulsed Power (HPP) drivers. In order to constrain Equation of State (EOS) and elastic-plastic behavior parameters, physical quantities such as wave velocity, temperature and pressure are valuable measurements. In our HPP driver experiments, wave velocities are routinely measured and temperature measurements can be obtained under certain conditions. Due to the severe electromagnetic environements associated with these experiments, fielding pressure gauges proved more difficult. However, such measurements are very useful for characterizing the dynamic response of the materials studied.. Hence, we studied the feasibility of a diagnostic based on ruby luminescence for HPP drivers. Ruby luminescence spectra were recorded during a microsecond  scale ramp-compression experiment on the ICE16 driver. A 0.5 mm thick ruby disk served as sample. The ruby luminescence was recorded using a CCD camera coupled to a dispersive spectrometer over 500 ns. Based on associated numerical simulations, a pressure of 4.06 GPa was inferred across the bulk of the ruby sample. During the recording period, the fluorescence spectroscopic measurements give a R1 shift of 0.73 nm.