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The spall strength and dynamic yield stress of polycrystalline hafnium have been measured in a series of plane-wave shock loading experiments using flat sample–transparent window composite targets, with the transparent windows representing polymethyl methacrylate or lithium fluoride plates arranged on the rear side of a hafnium sample. The front side of the target was subjected to shock impact of a copper striker, the rear surface velocity was measured, and the sample was recovered for subsequent metallographic examination. The results were also used for evaluation of the accuracy of spall strength measurements and the analysis of features of high-rate deformation of hafnium.

The microstructure of an ML5 commercial magnesium alloy reinforced by aluminum nitride (AlN) nanoparticles with an average size of 80 nm at an amount of 0.5 wt % has been studied. Comparative data on strength and plasticity of the initial ML15 alloy and AlN-reinforced metal-matrix composite were obtained using Instron 3369 universal testing machine. The influence of material microstructure on the resistance of samples to high-rate deformation and fracture was determined by analysis of the full wave profiles measured using a VISAR laser Doppler velocimeter.

Specific features in the deformation of polycrystalline vanadium under shock-wave loading conditions have been studied by experimental and theoretical methods. Analysis of the full wave profiles was used to determine the dynamic elastic limit and spall fracture stress in a range of stain rates of 105–107 s−1. The laws of elastic–plastic transition at the shock-wave front, mechanisms of elastic precursor relaxation, and spall fracture development are discussed.