ИСТИНА

The development of shock waves generators based on Mach reflection of shock wave started in early 1970s. In this presentation, the results of the last 10 years of our research are presented. A number of improvements has been introduced. Fully cylindrical design with sophisticated detonation distributor makes it possible to generate a conical imploding detonation wave using easy-to-made cylindrical geometry of the explosive charge and metal liner. Detonation distributor produced by the CNC milling machine provides perfect symmetrical convergence of the shock wave. The implemented double Mach reflection (DMR) regime provides flat and steady 1D shock wave in a sample. Besides, 2-staged generators have been developed, providing further rise of the shock parameters. The experimental development was supported by a 3D numerical simulation of explosion devices. Thus, a set of generators makes it possible to achieve pressures from 200 to 2,000 GPa, which can be compared with laser shock and electromagnetic launching techniques. In addition, a set of diagnostic tools was developed, including fast optical fiber-gauges measuring wave velocities and optical pyrometry. The results of the study of shock wave properties of the Earth mantle oxides, such as Al2O3, TiO2, MgO, FeO, are presented. In porous samples, shock compressibility was measured. In monocrystalline optically transparent samples the Hugoniot temperatures were also measured. The obtained data was compared with the calculated equations of state and other available experiments, and allowed us to draw some conclusions about high-pressure melting curves of the studied substances. Acknowledgements: This work was supported by the Ministry of Science and Higher Education of the Russian Federation (Institute for High Temperatures of the Russian Academy of Sciences, project No. 075-15-2020-785). All the experiments were carried out by using the equipment of Moscow Regional Explosive Center for collective use of the Institute of Problems of Chemical Physics RAS