The driving abilities of strong detonation in two stages explosive/flyer system have been studied by both analysis and experiments. Under certain condition, the system's geometric parameters are optimized in order to drive final flyer to high speed. The abilities of strongly detonating explosive slab in driving metallic flyers to high speed are shown in our calculation model. Calculated results agree with experimental results. The performances of strong detonation are illustrated. And numerical calculation shows that converging detonation can be an effective method to accelerate a flyer up to high speed.

Based on the Debye mode, electron gas model, and Grüneisen equation of sate, new formula were deduced which describe the individual contributions of lattice vibration and hot electron to shock temperature, shock pressure and compression volume of porous metals. It is found that the contribution of lattice vibration to shock compression volume accord with W-J equation; meanwhile, the contribution of hot electron to shock compression volume also can be calculated by the improved equation. In this paper, we especially discussed the reliability and the physical meaning of the new equations.

DFT-LDA method has been performed on calculations for fcc structure solid agon. The equation of state and adiabatic elastic properties of solid argon has been calculated up to 82 GPa. The results are in good agreement with the experimental data. The calculation indicates that the elastic properties and p-V relationship of solid argon can be obtained with local density approximation. If the parameters for calculation can be chosen properly, the elastic properties and p-V relationship of solid argon can be calculated exactly and save large of resource of computation at the same time.

In situ energy dispersive X-ray diffraction measurements on nano zinc sulfide shell have been carried out by using diamond anvil cell with synchrotron radiation. The highest pressure is 33.3 GPa in the experiment. The raw materials contain two structures of ZnS, which are wurtzite and zinc blende respectively. With increasing pressure, the wurtzite structre was transformed to zinc blende structure at 11.2 GPa. A phase transition from zinc blende structure to rocksalt structure occurred as the pressure reached to 16.0 GPa. Two unknown diffraction peaks were found in the range of pressure from 17.5 GPa to 21.0 GPa. The rocksalt structure existed as the pressure reached to 33.3 GPa. Both of the phase transitions are reversible.

The dynamic release behavior of OFHC copper under 10~20 GPa shock pressure was simulated by using the Johnson-Cook (JC) constitutive model and Steinberg-Cochran-Guinan (SCG) constitutive model, respectively. Comparisons between the simulations and the experimental results show that the strain rate effect during the release process of copper under such shock pressure ranges is still obvious. And the simulation of JC model gives better agreement with experimental results than the simulation of SCG model in which the strain rate effect is ignored.

Melting temperatures of OFHC (Oxygen-Free High Conductivity) copper at pressures ranging from 110 GPa to 140 GPa were measured on a two-stage light-gas gun by optical radiometry techniques and using LiF single crystal as window, based on such a conclusion that the melting temperatures at the sample/window interface pressure is equal to the release temperature, and close to the interfacial temperature if the OFHC copper sample is initially shocked or released into the region adjacent to the liquidus. The obtained data are consistent with the experimental results of high-pressure sound velocity measurements and theoretical predictions, and the melting behavior of OFHC copper at high pressure can be approximately described with Lindemann melting law. The method for melting temperature measurements we proposed in this paper avoided derivation of Hugoniot temperature, which simplified the determination of melting temperature, and provided a potential approach for melting temperature measurements of metals.

Raman scattering spectroscopy was used to investigate stability of n-pentane in Moissanite anvil cell from 0.07 GPa up to 4.77 GPa at ambient temperature. The result shows that CH₃ symmetric and asymmetric stretching vibration, CH₂ symmetric and asymmetric stretching vibration and -(CH₂)_n - in-phase twist mode at 2 877 cm^-1, 2 964 cm^-1, 2 856 cm^-1, 2 935 cm^-1 and 1 303 cm^-1, respectively, shifted to higher frequency according to quasi-linearity with pressure increase, and an abrupt visible change was taken place, indicating that it is a sort of phenomenon of freezing at overpressurization. In addition, a high-pressure transition phase may appear in crystallized n-pentane in the range of 2.84~4.77 GPa. The equilibrium freezing pressure of n-pentane is (1.90±0.05) GPa at 27 ℃ by measuring with the method of crystal-liquid coexistence.

In the framework of density functional theory, the static structure properties and phase transition of aluminium are calculated using the augmented plane wave plus local orbitals (APW+lo) method with generalized gradient approximation (GGA) for the exchang-correlation energy. The critical values for the phase transitions (fcc-hcp, fcc-bcc, hcp-bcc) are 220 GPa, 300 GPa and 380 GPa, respectively. Our results are in consistent with existing data obtained from different methods and also in good agreement with experiments.

The spectra of energy dispersive X-ray diffraction with synchrotron radiation of double perovskite compound Sr₂CrWO₆ have been studied in situ high pressure pressure up to 34.5 GPa using a diamond anvil cell at room temperature. The experimental results indicate that the sample undergoes a crystal structural change at about 9 GPa. The resistance-pressure and capacitance-pressure relationships in the pressure range of 0~20 GPa show that there is an electronic structural change in Sr₂CrWO₆ in the pressure range of 2~5 GPa.

Compared to the traditional numerical methods, meshless SPH method is more suitable to simulate the hypervelocity impact in that it can simulate the material interface clearly and overcome the numerical instability due to the large mesh deformation in the Lagrange method. In SPH, in order to get the physical value of one nodal at time t, it is firstly required to find the neighboring nodes interacting with it, so the calculation speed is slower and the calculation time is longer than that of the FEM. This paper adopts the coupling method of SPH and Lagrange to simulate the 3D hypervelocity impact problem. The results show that the coupling method can save largely time while keep the accuracy approximately to that of SPH.