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In this paper, based on numerical simulation method, the rosin-rammler method was introduced to describe the non-uniqueness of particle diameter of abrasive water jet nozzle and the two-way coupling method was used to simulate the interaction between discrete phase and continuous phase. Through CFD simulation software, the influence of nozzle convergence angle, focus tube length on the outlet velocity of mixed-phase, and the relationship between abrasive flow rate and nozzle inner wall wear were obtained.

An analytical method is proposed to evaluate the Hugoniot parameters of preheated metallic materials by relating to its principal Hugoniot. Modelling calculations for 1100 Al, Cu and Ta show that the preheating lowers to a certain extent the shock impedance and the degree of lowering the shock impedance increases with increasing preheating temperature. The Hugoniots of 6061-T6 A1 and TC4 preheated flyers at known preheating temperatures are evaluated, and are utilized to calculate the particle velocity and shock pressure using the impedance-match method based on the measured shock wave velocity and impact velocity reported in Z pinch-driven and three-stage gun-driven Hugoniot experiments. The presented method allows a reasonable evaluation for Hugoniot of the preheated metallic flyers.

Asymmetric plate impact experiments are conducted on LY12 aluminium alloy in a pressure range of 85–131 GPa. The longitudinal sound speeds are obtained from the time-resolved particle speed profiles of the specimen measured with Velocity Interferometer System for Any Reflector (VISAR) technique, and they are shown to be good agreement with our previously reported data of this alloy in a pressure range of 20–70 GPa, and also with those of 2024 aluminium reported by McQueen. Using all of the longitudinal speeds and the corresponding bulk speeds calculated from the Gruneisen equation of state (EOS), shear moduli of LY12 aluminium alloy are obtained. A comparison of the shear moduli in the solid phase region with those estimated from the Steinberg model demonstrate that the latter are systematically lower than the measurements. By re-analysing the pressure effect on the shear modulus, a modified equation is proposed, in which the pressure term of P/η1/3 in the Steinberg model is replaced by a linear term. Good agreement between experiments and the modified equation is obtained, which implies that the shear modulus of LY12 aluminium varies linearly both with pressure and with temperature throughout the whole solid phase region. On the other hand, shear modulus of aluminium in a solid-liquid mixed phrase region decreases gradually and smoothly, a feature that is very different from the drastic dropping at the melting point under static conditions.

The sound velocities along the release path of annealed LY12-Al are measured by using a velocity interferometer system for any reflector (VISAR) technique. The shear modulus and yield strength are then obtained. Comparison of the experimental results with those of unannealed LY12-Al shows that anneal has little influence on sound velocities and shear modulus though it weakens the yield strength considerably, and changes the dependence of yield strength upon shock stress. The ratio of shear modulus to yield strength of unannealed LY12-Al increases with shock stress monotonically while that of annealed LY12-Al exhibits much more complicated behaviour.

A velocity interferometer system for any reflector (VISAR) is used to measure the sound velocity of LY12 Al shock-compressed to peak pressures of 20, 32, 55 and 71 GPa. Unloading wave velocities from these pressures are obtained from the observed particle velocity profiles at the LY12 Al/LiF window interface; and the longitudinal, bulk and shear sound velocities at the initial Hugoniot state are well determined. The histories of stress, strain, density or volume, and particle velocity along the release paths are calculated by the impedance-matching method based on the unloading sound velocity data. It is revealed that the release behaviour of shocked LY12 Al departures obviously from the elastic perfectly-plastic response.