A series of impact tests were conducted to investigate the ballistic performances of single, double- and three-layered 45 steel plates subjected to impact by hemispherical-nosed projectiles which were made from 38CrSi and diameter was 12.7 mm, the impact velocities ranged from 240 m/s to 600 m/s. The multi-layered plates arranged in various combinations of the same total thicknesses were normally impacted with the help of a gas gun. The initial and residual velocities of the projectiles were measured, and also the ballistic limit velocity for each configuration target was obtained and compared based on the investigation of the effect of the number of layers on the ballistic resistance. The results indicated that the ballistic limit velocity of multi-layered plate was higher than that of monolithic plate. The dominant failure model of monolithic plate was shearing, but the dominant failure models of multi-layered plate were global dishing and local bulging. Moreover, the failure models of plates of multi-layered plates were in relation to their order.

Based on the analysis of shortcomings existed in quasi-δ function calibration method, a dynamic calibration method was proposed. In this method, a pressure sensor was under high static pressure in advance, and then a bullet was used to impact Hopkinson bar for generating a quasi-δ function signal with small amplitude, which excited the sensor being calibrated, and finally a frequency response characteristics of the sensor was obtained. The principle of quasi-δ function dynamic calibration method was introduced. The relation of pulse-width of quasi-δ function signal, calibrated frequency range, and calibration precision was analyzed. The dynamic calibration system was established. This calibration method realized dynamic calibration of high pressure sensor under actual working pressure, and realized the tracing from zero frequency to a certain frequency needed. On the current technical level, the maximum static pressure is 800 MPa, the pulse width of the quasi-δ function signal is within 7 μs to 10 μs, the calibrated frequency range is from 0 to 20 kHz, and calibration error of amplitude-frequency characteristics is 5%.

The anti-penetration property of the corrugated sandwich composite armor with the corrugation angle of 45° in different penetration angles was studied. The performance of the armors filled with rubber and without rubber was studied, based on the energy loss, DOP and quality protection factor considerations. The energy absorption characteristics of the armor filled with rubber was analyzed. The reliability of the simulation results was validated by Ø56 mm stander shaped charge penetrating the steel at 0° dip angle and the composite armor at 60° dip angle. The results showed that the protection capability of the corrugated sandwich composite armor with corrugation angle of 45° was effective. It's beneficial to fill the corrugation gaps with rubber. This kind of composite armor has excellent protection capability and can be used as a new kind of light armor.

The effect of dynamic high-pressure microfluidization (DHPM) treatment on vitamin C, the total polyphenol content and the antioxidant activity of fresh pineapple juice was studied. Results indicated that the vitamin C content decreased after DHPM treatment. Under the pressure of 30 MPa, the loss of vitamin C was most. The total polyphenol content in fresh pineapple juice showed different degree of reduction after DHPM treatment. Under the pressure of 60 MPa, the total polyphenol content was the lowest, which was about 383.19 mg/L. The antioxidant capacity of pineapple juice decreased after the different DHPM pressure treatment compared to the untreated one by phosphomolybdenum method and ferric reducing/antioxidant power assay.

The variations of the damping coefficient and molecule field with the pressure are investigated, and the quantitative forms are given in Ce: YIG crystal. The variations of the line width of iron magnetic resonance and the magneto-optic Faraday rotations with the pressure are presented. The calculated results are agreement with the measured values in the pressure range of 1.33-13.30 Pa. The investigation indicates the dependence of the magnetic and magneto-optic properties of Ce: YIG crystal on the pressure. It is important that the pressure should be controlled properly in the preparation of materials.

The large volume press (LVP) become more and more popular with the scientific and technological workers in the high pressure area, because it could generate relatively higher pressure, provide better hydrostatic pressure and could be utilized in conjunction with in situ X-ray diffraction, neutron diffraction and ultrasonic measurement. There have been generally two LVP techniques to generate high-pressure: the double-anvil apparatus and the multi-anvil apparatus (MAA). Hinge-type cubic presses, as the main apparatus in china, have been widely used in the fields of both scientific research and diamond industry. However, for a long time past, the maximum pressure using the conventional one-stage anvil system for hinge-type cubic press is about 6 GPa, and the techniques about two-stage apparatus (octahedral press) that could generate pressure exceed 20 GPa is blank in our country. To a certain extent, the backwardness of the LVP technology in china restricts the development of high pressure science and related subjects. In recent years, we designed two kinds of one-stage high pressure apparatus and the two-stage apparatus based on hinge-type cubic-anvil press, the one-stage high pressure apparatus and the two-stage apparatus using cemented carbide as anvils could generate pressures up to about 9 GPa and 20 GPa respectively. This article mainly reviews the mechanics structure, design of cell assembly, pressure and temperature calibration, design and preparation of the sintered diamond anvils and pressure calibration to 35 GPa using sintered diamond as two-stage anvils about the one-stage high pressure apparatus and the two-stage apparatus designed in our laboratory.

Based on one-stage light gas gun, series of experiments including oblique planar impact with inclination angles of 0~15° and impact velocity ranging from 68 to 201 m/s were carried out to investigate the responses of alumina microvoid ceramics with high porosity subjected to impact loading. Experimental results show that since the diameter of microvoid in sample is smaller than 5 μm, the process of sample compression is gradually and evenly developed, and there is no porous collapse observed. The dynamic shear behaviors are similar to those of brittle materials. Based on the Hoek-Brown criteria and Cap-model, the dynamic model for the failure surface and the double yield surfaces of porous brittle materials was built. Based on the experimental data of compression and shear combined impact loading, the preliminary analyses were carried out and the results show the applicability of the model.

Numerical simulation of aluminum sphere projectile high-velocity impacting aluminum mesh bumper was conducted with Smoothed Particle Hydrodynamics (SPH) arithmetic of LS-DYNA. The relationship between the debris clouds characteristic of projectile and the impact position on aluminum mesh bumper was studied. The effect on fragmentation of projectile from different combination mode of aluminum mesh bumper was analyzed. The results indicated that the debris clouds configuration from aluminum sphere projectile impacting aluminum mesh bumper was different with the different impact position on aluminum mesh bumper. The debris clouds as palpus was found in the front of projectile debris clouds. Some local kinetic energy concentrated appeared in the debris clouds. When a wire across point position was impacted, projectile debris clouds expand to form film configuration, and debris clouds distribution was more uniform. When aluminum mesh bumper was combined with interleaving mode, projectile debris clouds had more diffuse area and less residual kinetic energy. Aluminum mesh bumper combined with interleaving mode was helpful in enhancing the protection performance of shields.

Based on the 2-D motion model of bullet penetrating gelatin, a function of the drag coefficient, the lift coefficient, the roll moment coefficient and the yaw damping torque coefficient derivative which is related to the bullet shape is established. Based on the 7.62 mm bullet, five kinds of bullets were designed for the penetrating experiment by changing the caliber of ogive, the ratio of tail contraction and the length-diameter ratio of cylinder. The model was calculated based on the Runge-Kutta method and the calculation is compared with the experiment. The result shows that these four coefficients can describe the effect of the bullet shape on the motion. It will provide theoretical bases for the ammunition design.

The present numerical study is to investigate the explosive driven behaviors to the flight velocity and flight area of all the fragments of evolvable aimed warhead, and the propagating style of the detonation wave of the three-dimensional model. The results of numerical simulation demonstrate that the dual initiation that one eighth to the end of the axis has the best effect of the five initiation positions. Under the effect of the spherical explosive wave, the directional dispersion of the fragment of the three-dimensional model can be controlled well. The rationality of the numerical simulation was verified by the explosion experiments.