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Consideration is given to the setup and results of shock-wave experiments that recorded the longitudinal stress-wave profiles σxx in quartzite at the initial density ρ0 = 2.63 g/cm³. Profiles of the symmetric impact-induced stress waves were measured within 20–50 GPa by the method of the overtaking release wave in plane samples using manganin gauges built into quartzite. The objective of this effort is to measure experimentally the shock-wave properties of the rock, namely quartzite, as these results are needed to calibrate, further develop, and improve computer models of equations of state. This effort is of fundamental nature. Our task was to generate, with the help of low-resistance manganin gauges, profiles of longitudinal stresses σxx in quartzite sampled from the Pervouralsk deposit. Experiments were performed with the help of plane-wave generators and a two-stage light-gas gun. As a result, a series of experiments provided experimental “longitudinal stress – time” relations and the parameters of quartzite shock compression within 20–50 GPa, both being of great importance for the development of computer models. [ABSTRACT FROM AUTHOR]

The paper presents the results of studying the dynamic properties of a structural material, such as stainless steel made by additive fabrication (3D printing). In the study, the split Hopkinson pressure bar system is applied. This method allows us to test a wide range of materials and to study the dynamic diagrams of compression and strain within the strain rate range of ε˙ = 10²–10³ s−1. Specimens made of stainless steel (analogous to the 12Kh18N10T steel) are obtained by laser sintering of metal powder (Selective Laser Sintering) using an industrial 3D printer. Twelve experiments are conducted with the stainless steel specimens. The impactor velocities range from 7 to 14 m/s. The intrinsic strain rates of the specimens range from 0.75×10³ to 2.8×10³ 1/s. The study offers stress–strain and strain-rate –strain diagrams. The objective of the work is to study the properties of stainless steel specimens fabricated by additive techniques. The following tasks are to be solved: determining the strength characteristics of the specimens made of additive stainless steel in a set of experiments using the split Hopkins pressure bars technique; comparing the strength properties of additive stainless steel and its analogue, e.g. the conventional 12Kh18N10T steel. [ABSTRACT FROM AUTHOR]

The study was undertaken in order to obtain experimental data on shock compression of structural materials for the development and refining computational models of material and structure behavior under shock wave loading. Wave profiles of longitudinal stresses σxx in stainless steel of a specified grade were measured at the initial density ρ0 = 7.89 g/cm³. The stress wave profiles were measured using symmetric impact by the method of overtaking unloading wave in flat samples with the help of manganin sensors built in the metal or the buffer material. Sound velocities in shock-loaded stainless steel were determined using the obtained profiles σxx(t). Experimental data on sound velocities C(σ¹xx) vs. stress in a shock wave σ¹xx are provided. As a result of a series of experiments, experimental data on sound velocities in shock-loaded stainless steel of grade 12Cr18Ni10Ti were obtained in the range of initial values of shock compression of 10 ≤ σ¹xx≤88 GPa. [ABSTRACT FROM AUTHOR]

The paper presents a shear strength model used to evaluate information of interest from shock experiments aimed at studying the properties of the hardened 30KhGSA steel and the MA14 magnesium alloy subjected to low- and high-intensity loadings. The model parameters are adjusted by experimental deformation curves obtained from static and dynamic tests at different temperatures and the data from shock experiments to account for strength variation at high strain rates. The simulation of low-intensity loading tests helped to improve the description of elastic-plastic properties and to adjust our failure model. The data from the shock experiments with high-intensity loading of 30KhGSA steel samples and unloading of the shocked samples in window materials were used to verify the phase diagram and the kinetics of direct and inverse phase transitions, and to determine more exactly how the changed phase state influences the strength. The model presented here has allowed us to reproduce the complicated strength behavior of the MA14 alloy at different loading intensities. [ABSTRACT FROM AUTHOR]

The study is undertaken in order to obtain experimental data on dynamic compression of structural materials for refining computational models that describe material behavior under dynamic loading. The task was to study the dynamic properties of a copper-tin alloy and copper M00K in the strain rate range ε = 10² − 104 s-1 [ABSTRACT FROM AUTHOR]