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A heat conduction model for three parallel layers of dissimilar materials is proposed to describe the heat flow through the sample/μ m-size high-temperature layer/window after passage of a strong shock front. This model provides a possible approach to shock temperature measurements for metals using a disc sample. Using this model we derived a shock temperature or melting temperature of meteoritic iron based on the observed interfacial temperature by optical radiometry techniques. The data sets determined are in agreement with those measured using a film sample of stainless steel analogous to meteoritic iron in composition.

The sound velocities of vanadium at shock pressure ranging from 154 to 250 GPa were determined using transparent-window optical analyser techniques. A discontinuity in sound velocities at about 225 GPa may mark the partial melting under shock compression. The comparison between the measured sound velocity data sets above ~225 GPa and calculated values yields γ0≈2.0 and the empirical expression γρ = γ0ρ0 is basically tenable. Additionally, shock temperatures along the principal Hugoniot of vanadium were also determined from interfacial radiation intensities according to Grover's ideal interface model. Thus the temperature at this solid-liquid phase transition was constrained to be round about 7800(±800) K on the basis of the measured Hugoniot temperatures, melting temperatures, and high-pressure sound velocity variations with pressure.

Dynamic strength behavior of Zr51Ti5Ni10Cu25Al9 bulk metallic glass (BMG) up to 66 GPa was investigated in a series of plate impact shock-release and shock-reload experiments. Particle velocity profiles measured at the sample/LiF window interface were used to estimate the shear stress, shear modulus, and yield stress in shocked BMG. Beyond confirming the previously reported strain-softening of shear stress during the shock loading process for BMGs, it is also shown that the softened Zr-BMG still has a high shear modulus and can support large yield stress when released or reloaded from the shocked state, and both the shear modulus and the yield stress appear as strain-hardening behaviors. The work provides a much clearer picture of the strength behavior of BMGs under shock loading, which is useful to comprehensively understand the plastic deformation mechanisms of BMGs.