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Complementary gas‐gun and electromagnetic pulse tests conducted in Sandia's Dynamic Integrated Compression Experimental (DICE) Facility have, respectively, probed the behavior of electronic‐grade Kovar® samples under controlled impact and intermediate‐strain‐rate ICE (Isentropic Compression Experiment) loading. In all experiments, velocity interferometer (VISAR) diagnostics provided time‐resolved measurements of sample response for conditions involving one‐dimensional (i.e., uniaxial strain) compression and release. Wave‐profile data from the gas‐gun impact experiments have been analyzed to assess the Hugoniot Elastic Limit (HEL), Hugoniot equation of state, spall strength, and high‐pressure yield strength of shocked Kovar®. The ICE wave‐profile data have been interpreted to determine the locus of isentropic stress‐strain states generated in Kovar® for deformation rates substantially lower than those associated with a shock process. The impact and ICE results have been compared to examine the influence of loading rate on high‐pressure yield strength.

A series of gas‐gun experiments has probed the planar (uniaxial strain) impact response of six different commercial brazing alloys that were subjected to a peak shock stress in the range of 5.5 – 7.2 GPa. The alloys studied were copper + gold (65/35 wt%), copper + gold (50/50 wt%), Cusil®, Nicusil®‐3, Nicoro® + titanium (98/2 wt%), and silver zirconate. Both as‐received and annealed samples of each alloy were tested under ambient (room temperature) and preheated (100 C) initial conditions. Velocity interferometer data acquired during this investigation have been evaluated to determine the dynamic yield strength (i.e., Hugoniot Elastic Limit), shock Hugoniot state, and spall strength for baseline alloy samples (i.e., unheated, as‐received material) and for samples whose initial condition involved annealing and/or preheating.

Cadmium sulfide crystals were shocked along the c-axis to peak instantaneous stresses ranging from 27 to 53 kbar, above and below the phase transition stress of 32 kbar. Particle velocity measurements, using a VISAR system with nanosecond temporal resolution, were used to determine the time dependent mechanical response at the impact surface at higher time resolutions than those reported by Tang and Gupta, and to complement the recent electronic spectroscopy measurements. For experiments with longitudinal stresses above 32 kbar, but below 53 kbar, the instantaneous impact stress of the initial wurtzite phase is maintained for significant times before relaxing to a metastable state, and then further relaxing to the final rock salt phase. Transition rates and metastable state lifetimes are observed to be stress dependent. At 53.5 kbar impact stress, transition to a metastable state appears to be complete within 3 ns of impact, and the full relaxation to the rock salt phase indicates that the phase transition may proceed through multiple metastable states. Epoxy bonds with VISAR windows degrade the ability to accurately measure fast, stress-relaxing phenomena.