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Influence of Silicon Nitride Content on Explosive Performance of Bulk Emulsion Explosive
ZHU Zhengde, LIU Feng, KUANG Zhao, FU Jiakun
 doi: 10.11858/gywlxb.20251031
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Silicon nitride, with high nitrogen content, was added to improve the explosive performance of bulk emulsion explosive. Air blast experiments, detonation velocity tests, and lead column compression experiments were conducted to assess the impact of silicon nitride content on the air shock wave parameters, detonation velocity, and Brisance of bulk emulsion explosive. The results showed that as the silicon nitride content increased from 0 % to 1.2 %, the density of the explosive increased from 1.02 g·cm-3 to 1.11 g·cm-3. The air shock wave pressure peak increased from 0.1156 MPa to 0.2977 MPa, then decreased to 0.2408 MPa, with the maximum peak being 1.57 times the minimum peak. The specific impulse increased from 9.22 Pa·s to 23.00 Pa·s, then decreased to 19.59 Pa·s, with the maximum specific impulse being 1.49 times the minimum. The detonation velocity decreased from 3867.45 m·s-1 to 3265.66 m·s-1, then increased to 4830.60 m·s-1, before decreasing again to 4541.51 m·s-1, with the maximum detonation velocity being 1.47 times the minimum. The Brisance increased from 13.86 mm to 19.40 mm, then decreased to 17.18 mm, with the maximum Brisance being 1.40 times the minimum. The experimental results indicated that silicon nitride can enhance its explosive performance, providing valuable insights for the formulation and optimization of f bulk emulsion explosives.
Numerical Simulation of Rubberized Metaconcrete under Impact Load
ZHOU Rongxin, LIU Ye
 doi: 10.11858/gywlxb.20251005
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To enhance the dynamic performance of existing concrete-like materials, rubber aggregates were incorporated into a metaconcrete matrix to create a novel impact-resistant material, and the dynamic response of its mesoscopic mechanical model under impact load was simulated. Initially, the content, gradation, distribution, and appropriate material models of the specimen components were systematically calibrated and validated. Subsequently, the wave-damping capacity and the interaction patterns of the components in rubber-based metaconcrete under impact load were analyzed. In particular, the effect of rubber aggregates on the failure modes, damage zones, and extent of damage in metaconcrete under high-amplitude loads was thoroughly examined, and a parameter analysis of the rubber content and particle size was conducted. The numerical results showed that the addition of the rubber aggregates not only makes the damaged area of the concrete show dispersed characteristics, but also effectively mitigated the degree of specimen damage. Rubber aggregates enhance the specimen's toughness and suppress the intensification of damage. However, high rubber content has a detrimental effect on the specimen's strength, and leads to a trade-off between damage suppression and damage exacerbation. To balance these two effects, it is recommended that rubber aggregates make up 15% to 30% of the total volume of aggregates. These findings demonstrate that incorporating rubber aggregates into metaconcrete can significantly improve its dynamic performance. A reference can be provided for the design and engineering application of impact-resistant materials in future.
Mechanical behavior analysis of porous nested structures with negative Poisson's ratio
BAI Junzhe, LI Xinbo, DENG Qingtian, SONG Xueli, ZHAO Jianhua
 doi: 10.11858/gywlxb.20251021
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The deformation behavior and energy absorption characteristics of multilayer nested internal concave hexagonal monoclonal structures and tandem structures with different angles, spacing and connection modes are analyzed by using quasi-static uniaxial compression experiments, cyclic compression experiments and finite element numerical simulations. It is shown that the multilayer nested structure undergoes more shear deformation, and the stress distribution range is small and low, which is mostly concentrated in the diagonal bar connection; the monoclonal structure connected by the alternating mode with larger angle and smaller spacing has longer plateau period; the specimen with α=65° has better energy absorption and the isotropic connection and increasing spacing help to improve the energy absorption; the angle and spacing have the same effect on the plateau period of the tandem structure as that of the monoclonal structure, while the connection mode has the opposite effect; the angle and spacing have the same effect on the plateau period as the monoclonal structure, while the connection mode has the opposite effect. The effects of angle and spacing on the plateau period of the tandem structure are the same as those of the single-cell structure, while those of the connection mode are opposite; the increase of angle and spacing, and the change of the connection mode have a positive feedback with the energy absorption; the specimens are prone to delamination and plastic fracture under cyclic compression experiments, which are mostly appeared after the second cycle, and are accompanied by the stress softening and energy dissipation behaviors, and the effects are aggravated with the increase of the number of cycles.
Coupling Inhibition Effects of Dry Water Modified by Potassium Carbonate and Hexafluoropropane on Methane Explosion
WANG Tao, MENG Fan, YI Weizhai, TIAN Xiaoyue, LI Ruikang, SU Bin, LIU Litao, LUO Zhenmin
 doi: 10.11858/gywlxb.20240927
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Explosion suppression technology plays a vital role in reducing the hazardous effect of gas explosion incidents. This study aimed to investigate the explosion suppression effect of two-phase composite inhibitor mixtures of hexafluoropropane and dry water modified by potassium carbonate. The explosion pressure and time parameters of methane-air mixtures were obtained experimentally. Then the synergistic mechanisms on methane explosion suppression was analyzed theoretically. Results of the experiments shows that the combustion time of methane-air mixtures increase with the rising ratio of dry water modified by potassium carbonate in the coupled inhibitors. Dry water modified by potassium carbonate greatly enhanced the explosion suppression effect of C3H2F6. The critical inhibition ratios of gas-solid inhibitors are 5%-6 g, 3%-6 g, and 1%-4 g for fuel-lean, stoichiometric, and fuel-rich methane-air mixtures, respectively. Moreover, the physical inhibition effects of the dilution in the premixed mixtures and the reduction in the flame temperature, as well as the chemical suppression effect, synergistically inhibit the deflagration of methane-air mixtures. In terms of the chemical inhibition, it is KCO3, KOH, OH and fluorine-containing groups that produced by the pyrolysis of potassium carbonate and C3H2F6 reduce the concentration of key radicals of methane explosion. The results of the work will help to providing the theoretical basis for the development of more effective explosion-suppressant and promoting the related explosion-suppressing technology.

Dynamic Response Characteristics of Bridge Pile Foundation Structure Subjected to Blasting Vibration of Canal Excavation
HE Junhui, CHENG Tiejun, CHENG Chen, LIU Xianlin, JIANG Nan, SHAO Yu, LIU Yang
 doi: 10.11858/gywlxb.20251025
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Blasting excavation is an important construction method to improve the efficiency of canal channel expansion, but the blasting vibration effect caused by it may have adverse effects on the substructure of existing waterways. In order to clarify the dynamic response characteristics of the bridge substructure under the action of blasting excavation vibration, this paper analyzes the stress and vibration velocity distribution characteristics of the adjacent bridge substructure under the influence of blasting based on the Pinglu Canal channel expansion blasting project and the finite element numerical simulation method verified by field test. Based on the maximum tensile stress criterion, the safe vibration velocity threshold of the bridge substructure is proposed. The results show that the maximum tensile stress is generated at the junction of bridge pile foundation and cap under the vibration of canal blasting excavation. The parts with large vibration of the substructure are mainly located in the pile foundation. The allowable vibration velocity of the substructure of the bridge with the cap as the monitoring point is 3.2 cm·s-1.
A Dynamic Constitutive Model for Shear Thickening Fluid Impregnated Kevlar Fabric
YE Yichen, WEN Heming
 doi: 10.11858/gywlxb.20240968
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Shear thickening Fluid (STF) impregnated Kevlar fabric is a new type of composite materials which has better impact resistance as compared with neat Kevlar fabric. On the basis of previous work, a dynamic constitutive model for STF impregnated Kevlar fabric is firstly developed by introducing dynamic increase factor (strain rate effect) and residual strength factor in combination with the rheological properties of STF and yarn pull out test results. Numerical simulations of STF impregnated Kevlar fabric at different impact velocities are then conducted using the proposed constitutive model. Finally, the numerical results are compared with the relevant experimental data. It is shown that the present constitutive model can predict well the impact response of STF impregnated Kevlar fabrics in terms of residual velocity, load-displacement curve and damage morphology, lending support to the accuracy and usefulness of the dynamic constitutive model for STF impregnated Kevlar fabric.
Dynamic Response Experiment of Prefabricated Wall Panels for a Whole-Indoor Substation under Blast Loading
LI Lin, LIU Yong, WEI Zhenzhong, MA Xiaomin, LEI Jianyin, LI Shiqiang
 doi: 10.11858/gywlxb.20240873
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A novel prefabricated wall panel structure for substations was developed by integrating fiber cement board, aluminum honeycomb plate, and aluminum alloy plate. The dynamic response characteristics of the structure under explosive loads were investigated through experimental studies. The effects of overpressure loads at different explosive mass and loading distances were examined, and the impact of varying honeycomb cell sizes on structural deformation failure mode, back face deflection and strain, core compression, and fiber cement board crack distribution was analyzed. The results indicate that within a confined space, the time characteristics of explosion overpressure are similar to those in an unconfined space. The peak overpressure measured independently at the center is between 2.4 and 10.0 times that measured directly at the edge. The positive pressure duration measured independently at the center is between 0.44 and 0.71 times that measured directly at the edge. The predominant deformation mode of the structure involves front panel depression and rear panel bulging. Horizontal cracks in the front face of the fiber cement board are predominantly located near its long side boundary, while cracks in the back face are mainly distributed near its center and diagonal areas. Compared with structures featuring smaller honeycomb cell sizes, those with larger honeycomb cell sizes exhibit greater residual deflection on their back faces and longer total crack lengths in their fiber cement boards.

The response characteristics and deformation mechanism of sandwich tubes under lateral explosive loads
YANG Qiao, ZHANG Tianhui, LIU Zhifang, LEI Jianyin, LI Shiqiang
 doi: 10.11858/gywlxb.20251017
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The dynamic response and energy absorption performance of foam aluminum sandwich tubes under lateral explosive loads were systematically investigated using a combination of experimental research and numerical simulation. A series of lateral explosion experiments were conducted using a ballistic pendulum system to analyze the effects of structural geometric parameters, foam aluminum density, and the explosive mass on deformation mode and blast resistance performance. Based on the experimental results, numerical simulations were performed to further compare the blast resistance performance of foam aluminum sandwich tubes and circular tube core sandwich tubes, comparing gradient and non-gradient designs of circular tube core sandwich tubes. The results show that, the final deformation of circular tube core sandwich tubes is greater than that of foam aluminum sandwich tubes, though the difference is not significant. Among the gradient circular tube core sandwich tubes, the configuration with the largest outer wall thickness and the thinnest middle layer exhibits the best improvement in blast resistance performance. Furthermore, the blast resistance performance of gradient circular tube core sandwich tubes is significantly superior to that of non-gradient structures.
Rock burst prediction based on data preprocessing and improved sparrow algorithm
ZHANG Ding, ZHOU Zonghong
 doi: 10.11858/gywlxb.20240964
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To solve the problems of outlier samples, unbalanced samples, and local optimum of sparrow search algorithm in machine learning rockburst prediction, this paper established a rockburst prediction model from two perspectives of data preprocessing and algorithm improvement. First, based on lithology conditions and stress conditions, selected the maximum tangential stress, compression strength, tensile strength and elastic energy index of surrounding rock as the characteristic indexes, and used three kinds of machine learning algorithms combined with 5-fold cross-validation method to construct the prediction model. In the data pre-processing stage, collected 174 groups of domestic and international rock burst cases to establish a database; for outlier samples, introduced the local anomaly factor (LOF) algorithm to detect and eliminate outlier samples step by step according to the rock burst class; for sample imbalance, introduced the adaptive oversampling method (ADASYN) to increase the number of minority class samples.Three hybrid strategies were used to improve Sparrow search algorithm, and ISSA was used to optimize parameters of three machine learning algorithms, namely limit Gradient Lift Tree (XGBoost), Random forest (RF) and multi-layer perceptron (MLP). Multiple evaluation indexes such as accuracy rate and precision rate were analyzed and discussed to verify the effectiveness of the model. The results show that the accuracy of the newly constructed optimal model ISA-XGBoost reaches 94.12%, which has a high prediction accuracy. In addition to the feature importance analysis of the four feature indexes, it is determined that the maximum tangential stress of the surrounding rock is the most important feature.
Preparation, Microstructure and Mechanical Properties of Mo and Cocrfenimn High Entropy Alloy Hard Coating Layer
CUI Kaijie, WANG Jiangang, WANG Hefeng, XING Xuegang, XIAO Gesheng, JIA Yiwei
 doi: 10.11858/gywlxb.20240966
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To address the issue of low hardness and limited service life of Invar alloy in practical applications, this study employs the double-glow plasma surface alloying (DGPSA) technique to fabricate Mo and CoCrFeNiMn hard coatings on the surface of Invar alloy. The phase structure, microstructure, and element distribution of the two coatings are investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). The effects of loading strain rate on surface hardness, elastic modulus, and creep behavior of the two hard coatings are systematically studied via nanoindentation. The thickness of the Mo coating is approximately 8.3 μm, with a dense and uniform internal structure and a body-centered cubic (BCC) structure. The CoCrFeNiMn coating is about 10 μm thick, with some internal porosity, and exhibits a face-centered cubic (FCC) structure. Nanoindentation experiments reveal that the hardness of the Mo and CoCrFeNiMn coatings is 15.49 GPa and 8.18 GPa, respectively, while their elastic modulus are 278.7 GPa and 227.12 GPa. Both hard coatings significantly enhance the surface hardness and elastic modulus of the Invar alloy, and both exhibit sufficient toughness. The hardness of both coatings increases with increasing strain rate, showing a pronounced strain rate sensitivity, while the elastic modulus remains relatively stable. Additionally,the creep behavior of both coatings is influenced by the applied strain rate, with nanoindentation creep primarily governed by dislocation motion. The modification effect of the Mo coating is superior to that of the CoCrFeNiMn coating.
Study and Preliminary Application of the Equation of State of C3N4
CHEN Yulan, PEI Hongbo, GUO Wencan, LIU Fusheng, GAN Yundan, LI Xinghan
 doi: 10.11858/gywlxb.20251006
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C3N4 has a wide range of applications in the synthesis of superhard materials and photocatalysis materials, but its phase transitions and physical behaviors under high pressure and high temperature conditions are not fully understood. Therefore, it is necessary to study its thermochemical equation of state. In this paper, a novel, high-precision and low-cost method is proposed for quantitatively determining the equation of state of C3N4, based on decomposition phase boundary and compression line at room temperature. This paper constructs equation of state for two phases of C3N4, and the corresponding physical quantities match well with first-principles calculations and experimental values, proving the reliability of the equation of state. Based on the equation of state of C3N4, this paper made a preliminary judgment on the phase state of the controversial points. Furthermore,this study attempts to incorporate the equation of state of C3N4 into the research on the detonation mechanism of the novel nitrogen-rich explosives. It significantly reduced the long-standing errors between the calculated values and experimental values of the detonation parameters of the explosives, and provides a new reference direction for the research on the detonation parameter calculations of new explosives.
Interface proximity effect on the evolution of a shock-accelerated heavy gas cylinder
YANG Huanhuan, ZHANG Enlai, LI Xinzhu, ZOU Liyong
 doi: 10.11858/gywlxb.20251008
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To uncover the interface proximity effect arising from the interaction between shock wave and near-surface hole, defect, as well as impurity in material in practical application, a simplified mechanism study on the influence of downstream planar heavy-light interfaces on the evolution of a shock-accelerated heavy gas cylinder was carried out through numerical simulation. The findings reveal that when the incident shock impinges upon the heavy gas cylinder, it gives rise to diffracted and transmitted wave systems. These wave systems then interact with the downstream planar slow-fast interface, leading to the formation of wave systems that reflect back and forth between the gas cylinder and the downstream planar slow-fast interface. Significantly, these wave systems not only govern the evolution of the gas cylinder interface but also trigger the generation of jets at the downstream planar slow-fast interface. Under diverse interfacial spacing conditions, the type of reflected waves originating from the diffracted wave system outside the gas cylinder varies at the downstream interface. This, in turn, modifies the sequence in which the reflected wave system and the focused wave system inside the gas cylinder interact with the interface of the gas cylinder. When the interfacial distance is narrow, the gas cylinder jet can permeate the gap fluid sandwiched between the gas cylinder and the downstream slow-fast interface. This penetration, in conjunction with the coupling with the jet at the downstream planar slow-fast interface, bolsters the evolution of the gas cylinder jet. As the interfacial distance increases, the jet coupling phenomenon progressively wanes, and the gas cylinder jet succumbs to the inhibitory effect of the vortex pair within the gas cylinder. With a further augmentation in interfacial distance, the gas cylinder jet experiences a promotional impetus due to the stretching effect of the rarefaction wave system reflected by the downstream interface. Quantitatively, the numerical simulation results unambiguously demonstrate that, irrespective of the interfacial spacing variations, the presence of a downstream planar slow-fast interface invariably augments the development of interfacial width, height, as well as circulation deposition.
Sensitivity Analysis and Determination of Some Parameters of the Rock RHT Model
LI Hongchao, WANG Fuqi, ZHANG Ji, LIANG Rui, WEN Yiming
 doi: 10.11858/gywlxb.20240965
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The RHT model (Riedel-Hiermaier-Thoma model) is extensively used in the numerical simulation and analysis of phenomena such as explosive impacts and penetration.The accuracy of the simulation results is primarily dependent on the constitutive model and the parameter values used within it.To perform sensitivity analysis and parameter determination for the parameters B, gt *,e0c ,e0t , ec and et in the RHT model for various rock types, LS-DYNA is employed to simulate projectile penetration into a target and SHPB impact tests under single-factor variations.The effects of changes in parameter values on the simulation results are analyzed, followed by an orthogonal experiment to assess the interaction effects between parameters and determine the optimal parameter values.The results indicate that the sensitivity ranking of the parameters B, gt *, e0c, e0t, ec and et varies under different operational conditions, and the effects of these parameters on the elastic, linear strengthening, and damage-softening stages of the SHPB impact curve are identified.Further orthogonal SHPB impact simulation experiments confirm the absence of interaction between these parameters, validating that the single-factor sensitivity analysis results are effective.The optimal values for these parameters in the RHT models of granite, red sandstone, and marble are determined.This finding provides valuable insights for the sensitivity analysis and parameter determination in rock-type RHT models.
Indentation behavior of CoCrFeNiMn high-entropy alloys under dynamic loads
WU Kunkun, LIU Cong, SU Buyun, QIU Ji, SHU Xuefeng, KANG Zhengdong
 doi: 10.11858/gywlxb.20251002
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To address the challenge of evaluating the internal stress of materials or structures in service environments, a method combining finite element analysis and micro-indentation testing is proposed. Taking the CoCrFeNiMn high-entropy alloy as the research object, compression, shear and micro-indentation tests were carried out under different loading speeds respectively. Based on the asymmetric initial yield function, Swift hardening and the associated flow rule, the elastoplastic constitutive model of this material was established. The constitutive model was programmed by using the stress integration algorithm and interfaced with the ABAQUS finite element software. Furthermore, by comparing the finite element simulation results and experimental results of the split Hopkinson pressure bar (SHPB) and the indentation model, the reliability of the model was verified. Based on the SHPB model, the numerical simulation of the dynamic compression experiment was carried out, and the stress fields at different dynamic deformation moments were imported into the indentation model as the initial stress (internal stress) fields for indentation simulation analysis./t/nThe results show that the initial stress field in the loading stage will significantly reduce the indentation load at the same indentation depth, and the reduction amplitude increases with the increase of stress. In addition, the existence of the initial stress field will further weaken the stress concentration during the indentation process. Through the quantitative analysis of the indentation displacement-load curves under different compression amounts, the indentation response laws of materials under different initial stress conditions were revealed. The research results provide a reference for the evaluation of the internal stress of materials or structures under service conditions.
Cover
2025, 39(3): 1-1.  
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2025, 39(3): 1-2.  
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Cover Feature
Shock-Induced Desulfurization of Natural Pyrite and Its Implications for the Early Earth’s Environment
WU Jie, GAN Bo, SONG Wenhao, TANG Canlian, ZHANG Youjun
2025, 39(3): 030101.   doi: 10.11858/gywlxb.20240916
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Meteorite impact events are considered as important influences on the composition of Earth’s early atmosphere, with substantial implications for biological evolution. The physicochemical behavior of sulfur-bearing minerals during such natural impact events is crucial for understanding the role of sulfur in the evolution of Earth’s ocean-atmosphere system. Here, we conducted shock recovery experiments on natural pyrite (FeS2) under shock pressures of approximately 20 and 55 GPa to investigate its decomposition characteristics under high-velocity impact. The experimental results indicate that pyrite undergoes partially decomposition into pyrrhotite and sulfur at the shock pressure of about 55 GPa, revealing its thermodynamic instability and the release of sulfur vapor. Our results suggest that the desulfurization of pyrite during meteorite impacts may contribute to the release of sulfur gases into oceanic and atmospheric systems. Such environmental changes may be linked to the Permian-Triassic mass extinction event approximately 250 million years ago, providing important insights into the biological crises of that era.

Physical Property and Structure
Pressure Distribution Investigation in Silicon Oil Compressed in Diamond Anvil Cell
XU Tiancheng, DENG Yuanhao, HONG Chen, HUANG Haijun, XU Feng
2025, 39(3): 031101.   doi: 10.11858/gywlxb.20240860
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Diamond anvil cell (DAC) is a kind of widely used static-high-pressure device. Benefitting from its wide pressure range, excellent optical applicability and convenience of use, DAC provides a tremendous boost to the development of high-pressure science. However, at high pressures, factors like solidification of pressure transmitting medium may cause destruction of the hydrostatic pressure condition in the DAC sample chamber, leading to the generation of pressure gradients. In this work, a new method of using the technique of picosecond ultrasonics to investigate acoustic signal distribution at various locations within the sample chamber was proposed, which can analyze the pressure distribution via the acoustic observations. Limitations in the continuity of signal acquisition, sample selection, etc. can be overcome in this experimental technique, which could be built and manipulated in an ordinary laboratory. Here, pressure gradient in silicon oil was carried out under compression using this technique, and the results revealed that the pressure gradient in the sample chamber increased from 1.3×10−4 GPa/μm at 1 GPa to 5.3×10−2 GPa/μm at 30 GPa. In addition, the anomalous change of standard deviation of the pressure distribution was analyzed by combining it with in-situ Raman spectroscopy, then the possible phase transitions of silicone oil at high pressures were discussed.

Performance Characterization of CO2 Phase Change Excitation Agent under the Synergistic Effect of Titanium Powder Content and Zero Oxygen Balance
DU Mingran, LI Weiwei, WANG Yinjun, YANG Haibin, LI Jihong
2025, 39(3): 031301.   doi: 10.11858/gywlxb.20240866
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To improve the performance of the CO2 phase change excitation agent, titanium powder with mass fractions of 2%, 4%, 6%, 8%, and 10% was added to the excitation agent. The contents of ammonium oxalate and salicylic acid were controlled to adjust the zero oxygen balance, respectively. The ignition reliability, pressure performance, thermal decomposition characteristics, safety performance and temperature resistance property were investigated by on-site ignition tests, thermogravimetric analysis, temperature resistance performance tests and theoretical calculations. The results show that: all the excitation agents are successfully ignited inside the tube after adding titanium powder with mass fractions of 2%, 4%, 6%, and 8%. The peak pressure is directly associated with the heat release amount of the excitation agent. Within the addition range of this test, the excitation agent with 8% titanium powder has the best pressure performance inside the tube. After adding titanium powder with a mass fraction of 8%, the peak pressures of excitation agent without adjusting the oxygen balance, with adjusting the zero oxygen balance through ammonium oxalate, and with adjusting the zero oxygen balance through salicylic acid increase by 11.81%, 14.27%, and 17.85%, respectively. The apparent activation energies of the three samples decrease by 5.96 kJ/mol, increase by 33.47 and 6.80 kJ/mol, respectively, indicating that adjusting the zero oxygen balance can optimize the thermal stability of the excitation agent. After adding titanium powder with a mass fraction of 8%, the safety of the excitation agent is good, and the temperature index Ts is above 90 ℃.

Effect of Water Content on the Performance of Porous Granular Ammonium Nitrate On-Site Mixed Ammonium Amine Explosive
LI Tianhao, WU Hongbo, WANG Quan, HUANG Wenyao, SUN Yanchen, NIU Caoyuan, HUANG Guoshu, YE Ziyang
2025, 39(3): 031302.   doi: 10.11858/gywlxb.20240885
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In order to study the effect of water content on the performance of porous granular ammonium nitrate on-site mixed ammonium amine explosives, five groups of on-site mixed ammonium amine explosives with different water contents were prepared by controlling the water content in the aqueous phase. We used scanning electron microscope to observe the internal microstructure of porous granular ammonium nitrate, and Brinkley-Wilson method to carry out theoretical calculations on the heat of detonation and detonation velocity of the explosives. The solubility of porous granular ammonium nitrate at different water contents was tested, and the viscosity of the ammonium amine explosive matrix, the immersion conductivity and the detonation velocity were tested. The results show that with the increase of water mass fraction from 9% to 17%, the mixing homogeneity of ammonium amine explosive matrix increased, the initial viscosity decreases from 218539 mPa·s to 99443 mPa·s; the conductivity of the explosive immersed in water with different water content for 3 h first decreased from 1.416 mS/cm to 1.234 mS/cm, and then increases to 2.600 mS/cm; the theoretical detonation velocity decreases from 4943 m/s to 4716 m/s; the actual detonation velocity is affected by the content of solid ammonium nitrate, first increasing from 3376 m/s to 3676 m/s, and then decreasing to 3631 m/s. In actual production, the mass fraction of water in on-site mixed ammonium amine explosives should be controlled at approximately 13%. At this water content, the explosives exhibit optimal water resistance, and achieve a relatively high actual detonation velocity.

High Pressure Technology
Calculation and Numerical Simulation of Winding Discreted Large Cavity of Ultra-High Pressure Die
ZHAO Liang, LI Mingzhe, WU Nannan, WANG Jinlong, LIANG Xiaobo, GU Zhouzhi, LI Huaiyong
2025, 39(3): 033301.   doi: 10.11858/gywlxb.20240851
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In order to improve the ultimate pressure bearing capacity and increase the volume of the cavity of the belt type ultra-high pressure die, a structure of winding discrete type large cavity ultra-high pressure die was proposed. This die is mainly composed of discreted cylinder, supporting ring and steel wire winding layers. The circumferential stress of the integral cylinder is eliminated in discrete structure and there is no need to use large size cemented carbide and supporting ring, which can effectively improve the pressure bearing capacity of high pressure die, reduce the difficulty of its manufacturing, and make it easy to obtain large cavity volume. The key parameters of the structure of high pressure die are designed and calculated to determine the optimal size of the geometry. It is found that under the same working internal pressure loading in numerical simulation, the stress of the discrete cylinder is lower, and the stress environment on the inner wall of the cylinder is effectively improved. The pressure bearing capacity of the winding discrete large-cavity ultra-high pressure die is predicted. It is found that the pressure bearing capacity of the die gradually increases with the increase of the number of discrete blocks, but the growth rate is slower and slower. Therefore, it is not feasible to increase the pressure bearing capacity of the cylinder by increasing the number of discrete blocks infinitely. The analysis shows that the winding discreted large cavity ultra-high pressure die has higher pressure bearing capacity, longer life and lower operating cost. It provides a new idea and method for the design of high pressure device with large volume and high pressure bearing capacity.

Dynamic Response of Matter
Damage and Breakage Characteristics of Loaded Coal Impacted by High-Pressure Pulse Water Jet and Its Influence Factors
FENG Renjun, ZHU Yongjian, DENG Fei, HE Jing
2025, 39(3): 034201.   doi: 10.11858/gywlxb.20240854
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To elucidate the evolution laws of impact velocity of high-pressure pulse water jet and the breakage characteristics of coal under confining condition, a coupled smoothed particle hydrodynamics-finite element (SPH-FEM) algorithm is adopted. A sinusoidal velocity is applied to the plunger inside the pipeline. The evolution laws of water jet velocity inside and outside the nozzle were obtained, and the temporal damage and breakage characteristics of coal under load and unload conditions impacted by pulse water jet were compared and analyzed. The influence of key parameters such as average velocity, pulse amplitude, and pulse frequency on damage and breakage characteristics of coal was revealed. The results show that the velocity evolution of water jet particles inside and outside the nozzle undergoes four stages: a stationary stage and transient acceleration to a low speed in the pipeline, acceleration inside the convergent section of the nozzle, micro-acceleration inside the straight section of the nozzle, and pulse variation speed following a sinusoidal variation after exiting the nozzle. Under the stress free and two-dimensional stress load conditions, the broken pits of coal specimen exhibit an abnormal development, and undergoes from bowl shape to U-shape, respectively. Two-dimensional stress load has a suppressive effect on the derivation and propagation of internal cracks in coal, reducing the rock-breaking efficiency. Besides, pulse water jet has a higher rock-breaking efficiency on loaded coal specimens than that of continuous water jet. The depth and area of coal fragmentation increase exponentially with the increase of plunger’s average velocity or pulse amplitude, and show a trend of initial increase and subsequent decrease with the increase of pulse frequency, indicating the existence of an optimal pulse frequency for coal fragmentation. The research findings could provide a theoretical guidance for improving the rock-breaking efficiency of high-pressure pulse water jet under confining conditions and optimizing the working parameters.

Close-Range Blast Resistance and Analytical Methods of Polyurea Coated Masonry Infill Walls with Built-in Tie Reinforcement
LI Yishuo, WANG Wei, XU Zhaowei, ZHANG Congkun, ZHANG Zhonghao, ZHANG Qiang
2025, 39(3): 034202.   doi: 10.11858/gywlxb.20240892
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In order to investigate the dynamic response process, damage characteristics and damage mode of polyurea coated masonry infill walls with built-in tie reinforcement under close-range explosion load, a series of close-range explosion tests were performed on masonry wall with different polyurea coating methods and thicknesses. Additionally, numerical studies were carried out using the LS-DYNA software. Based on the resistance function of the brick wall, steel bar and polyurea coating, an improved equivalent single degree of freedom (ESDOF) theoretical calculation model was established. This model can accurately describe the displacement response of the polyurea coated masonry infill walls with built-in tie reinforcement under close-range explosion load. Three damage modes: surface mortar layer damage, open pit dislocation with back bulge, and penetration damage were identified according to the wall’s out-of-face response characteristics during close-range explosion load. With the increase of the number of tension reinforcement, the anti-explosion performance of the wall improves and the critical penetration damage charge increases.

High Pressure Applications
Numerical Simulation on Damage and Failure of Metro Structure under Penetration and Explosion Effects
WANG Yin, SUN Jie, ZHAI Yongchao, SUN Liuyang, JIANG Yating, ZONG Xianghua, YANG Taochun, XIE Qun
2025, 39(3): 035101.   doi: 10.11858/gywlxb.20240877
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Taking Shuitun North Road Station of Jinan Rail Transit Line 7 as an example, a numerical simulation study was conducted to investigate the structural damage and failure effects of the metro structure based on the fluid-structure couple and full restart algorithm in LS-DYNA software. This study focused on two scenaries: projectile penetration followed by an explosion from outside to inside, and the inner explosion of a large equivalent TNT charge. Firstly, the accuracy of the numerical simulation and the selection of material model parameters were validated through the penetration followed by explosion test. Then, three cases of two-dimensional numerical model for penetration followed by explosion from outside to inside and three cases of three-dimensional numerical models for internal explosion were established. The damage mode of the metro structure and the damage condition for personnel and auxiliary components were analyzed. The simulation results demonstrate that the failure mode of the metro structure subjected to projectile penetration followed by explosion was localized damage. When the explosion occurs inside the metro structure, the peak of overpressure decays faster in the area close to explosion and slower in the middle and far area of the explosion. The present research results can provide a reference for further studies on the radial and normal shock wave propagation attenuation laws of the metro structure subjected to internal explosion.

Effect of Injection Pressure on Gasoline Deflagration Characteristics in Internal Combustion Engine
LI Run, CHENG Yangfan, ZHANG Beibei, LI Shizhou, LI Meng
2025, 39(3): 035301.   doi: 10.11858/gywlxb.20240857
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Abstract:

In order to explore the influence of injection pressure on the deflagration characteristics of gasoline in the confined space, a 20 L spherical explosion test device was used to examine the changes of characteristic parameters, i.e., the transient flame propagation and temperature of gasoline mist deflagration under different injection pressures. The results showed that the optimum spraying time was 100 ms, and the maximum explosion pressure and maximum explosion pressure rise rate increased linearly with the increase of injection pressure, while explosion duration decreased linearly. The change of injection pressure had a more significant effect on explosion duration, and the combustion efficiency of gasoline increased significantly with the increase of injection pressure. Based on the colorimetric temperature measurement method, the flame temperature field was reconstructed. It was found that the maximum average temperature had a linear relationship with injection pressure, and the maximum average temperature increased with injection pressure. The influence of injection pressure on the deflagration characteristics of gasoline mist was analyzed through the changes of mist morphology and flame temperature during flame propagation. The outcome of this research can provide theoretical reference for the design of turbocharged direct injection internal combustion engine and the improvement of combustion efficiency and economy of gasoline internal combustion engine.

Experimental Study of the Effect of Shear Stress on Phase Transition in c-Axis CdS Single Crystal under Dynamic Loading
TANG Zhi-Ping, Gupta Y M
1989, 3(4): 290-297 .   doi: 10.11858/gywlxb.1989.04.005
[Abstract](13684) [PDF 8643KB](2234)
Abstract:
For a long time, the problem whether shear stress affects the phase transition initial pressure is not well solved. Duvall and Graham suggested that cadmium sulfide (CdS) crystal could be used to study the effect of shear stress on the initial pressure of phase transition in c-axis CdS single crystal specimens under high velocity impact systematically. The axial stress of initial phase transition measured is T=(3.250.1) GPa, corresponding to a mean pressure pT=(2.290.07) GPa, which agrees the value 2.3 GPa of static results quite well within the experimental error. The shear stress in this case, T=0.72 GPa, is as high as 31.5% of the mean pressure. This result shows that the mechanism of phase transition may be assumed only to relate to a critical mean pressure or critical thermodynamic state, and the effect of shear stress can be ignored.
Flattening of Cylindrical Shells under External Uniform Pressure at Creep
Shesterikov S A, Lokochtchenko A M
1992, 6(4): 247-253 .   doi: 10.11858/gywlxb.1992.04.002
[Abstract](9588) [PDF 2836KB](1982)
Abstract:
Experimental studies of the deformation of cylindrical shells under creep to fracture conditions are described in this paper. Analyses of three series of test shells are given and experimental and theoretical results are compared with each other.
The Generation of 90 GPa Quasi-Hydrostatic Pressures and the Measurements of Pressure Distribution
LIU Zhen-Xian, CUI Qi-Liang, ZOU Guang-Tian
1989, 3(4): 284-289 .   doi: 10.11858/gywlxb.1989.04.004
[Abstract](15571) [PDF 6073KB](2648)
Abstract:
Quasi-hydrostatic pressures up to 90 GPa were obtained at room temperature in the diamond cell by using solid argon as pressure medium. The pressure distribution was determined by measuring the special shift of the R1 line of ruby at different positions within the sample chamber. Experimental results showed that the pressure differences (p) between the pressures at each point within the chamber and the mean pressure (p) were very small, ratios of p/p were less than 1.5% when below 80 GPa. The shape of ruby R lines at 90 GPa is similar to that at ambient pressure. Thus, quasi-hydrostatic pressure near 100 GPa can be obtained by using solid argon as pressure medium. Moreover, the red shifts with pressures of the peak positions at 14 938 and 14 431 cm-1 in ruby emission spectra, were also examined. It concluded that the line, 14 938 cm-1, can be adopted in the pressure calibration.
A Study on Calculation of the Linear Thermal Expansion Coefficients of Metals
ZHENG Wei-Tao, DING Tao, ZHONG Feng-Lan, ZHANG Jian-Min, ZHANG Rui-Lin
1994, 8(4): 302-305 .   doi: 10.11858/gywlxb.1994.04.010
[Abstract](16247) [PDF 1350KB](1137)
Abstract:
Based on the expression of pressure at temperature T and in terms of the universal equation of state Debye model and the thermodynamic relations, a general expression for the calculation of the linear thermal expansion coefficients of metals is obtained. This formula applied to the calculation of Al, Cu, Pb. Calculated results are in good agreement with the experiments.
Development of Large Volume-High Static Pressure Techniques Based on the Hinge-Type Cubic Presses
WANG Hai-Kuo, HE Duan-Wei, XU Chao, GUAN Jun-Wei, WANG Wen-Dan, KOU Zi-Li, PENG Fang
2013, 27(5): 633-661.   doi: 10.11858/gywlxb.2013.05.001
[Abstract](14378) [PDF 12118KB](1041)
Abstract:
The large volume press (LVP) becomes 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.
Research on Deformation Shape of Deformable Warhead
GONG Bai-Lin, LU Fang-Yun, LI Xiang-Yu
2010, 24(2): 102-106 .   doi: 10.11858/gywlxb.2010.02.004
[Abstract](8469) [PDF 1765KB](351)
Abstract:
Basing on the detonation theory, the structure of the deformable warhead was simplified to be double layer cylindrical shells under the detonation. Plastic hinges were introduced into the loading section of the shell, which contacted with the deforming charge, and the deforming charge was divided into small segments accordingly. Loading and movement of these segments were analyzed. Deforming shape of the cylindrical shell under the loading with equal distribution was bulgy, and the displacement of shell segments was obtained. Deforming charge with different thickness, according to the displacement of the segment, was set up to realize the same displacement of the shell segments on the loading direction. The D-shape was achieved theoretically, and the shape of deforming charge was designed accordingly. Numerical simulation validated the feasibility of the designed plan. The results indicate that the deformable warhead with the new-designed deforming charge can realize the D-shape.
The Failure Strength Parameters of HJC and RHT Concrete Constitutive Models
ZHANG Ruo-Qi, DING Yu-Qing, TANG Wen-Hui, RAN Xian-Wen
2011, 25(1): 15-22 .   doi: 10.11858/gywlxb.2011.01.003
[Abstract](17585) [PDF 689KB](1030)
Abstract:
The analyzed and calculated results indicate that the concrete failure strength will decrease under higher hydrostatic pressure, when the original failure parameters of HJC and RHT models implemented in LS-DYNA and AUTODYN are adopted. A new method is introduced which using the characteristic strength of concrete to confirm the modified failure parameters of HJC and RHT models. The same physical experiment of concrete penetration was simulated using the modified HJC and RHT failure parameters respectively, and the numerical results demonstrated that the RHT model matched the experiments much better. But the numerical results with the HJC modified failure parameters were not enough satisfied, because the third invariant of the deviated stress tensor was not considered in the HJC model.
Recent Progresses in Some Fields of High-Pressure Physics Relevant to Earth Sciences Achieved by Chinese Scientists
LIU Xi, DAI Li-Dong, DENG Li-Wei, FAN Da-Wei, LIU Qiong, NI Huai-Wei, SUN Qiang, WU Xiang, YANG Xiao-Zhi, ZHAI Shuang-Meng, ZHANG Bao-Hua, ZHANG Li, LI He-Ping
2017, 31(6): 657-681.   doi: 10.11858/gywlxb.2017.06.001
[Abstract](11365) [FullText HTML](4812) [PDF 2527KB](4812)
Abstract:

In the last 10 years or so, nearly all major Chinese universities, schools and research institutes with strong Earth science programs showed strong interest in developing a new research branch of High-Pressure Earth Sciences.As a result, many young Chinese scientists with good training from the universities in the west countries were recruited.This directly led to a fast growing period of about 10 years for the Chinese high-pressure mineral physics research field.Here we take the advantage of celebrating the 30th anniversary of launching the Chinese Journal of High Pressure Physics, and present a brief summary of the new accomplishments made by the Chinese scientists in the fields of high-pressure mineral physics relevant to Earth sciences.The research fields include:(1) phase transitions in the lower mantle; (2) high spin-low spin transitions of iron in lower mantle minerals; (3) physical properties of the Earth core; (4) electrical measurements of rocks; (5) electrical measurements of minerals; (6) elasticity of minerals (especially equation of states); (7) high-pressure spectroscopic studies; (8) chemical diffusions in minerals; (9) ultrasonic measurements under high pressure; (10) physical properties of silicate melts; (11) geological fluids.In sum, the last 10 years have seen a rapid development of the Chinese high-pressure mineral physics, with the number of scientific papers increasing enormously and the impact of the scientific findings enhancing significantly.With this good start, the next 10 years will be critical and require all Chinese scientists in the research field to play active roles in their scientific activities, if a higher and advanced level is the goal for the Chinese mineral physics community.

Modification of Tuler-Butcher Model with Damage Influence
JIANG Dong, LI Yong-Chi, GUO Yang
2009, 23(4): 271-276 .   doi: 10.11858/gywlxb.2009.04.006
[Abstract](10902) [PDF 402KB](812)
Abstract:
A modificatin of Tuler-Butcher model including damage influence was presented, which was incorporated into a hydrodynamic one-dimensional finite difference computer code, to simulate the process of spall fracture of 45 steel and Al-Li alloy. The calculated results are in good agreement with experimental data, and shows the correctness of the model.
Experiment and Numerical Simulation of Cylindrical Explosive Isostatic Pressing
CHEN Lang, LU Jian-Ying, ZHANG Ming, HAN Chao, FENG Chang-Gen
2008, 22(2): 113-117 .   doi: 10.11858/gywlxb.2008.02.001
[Abstract](13770) [PDF 1180KB](847)
Abstract:
The experiments of cylindrical explosive isostatic pressing were carried out. The internal temperatures in pressed explosives were measured by thermocouples. A thermal/structural coupled model of the explosive isostatic pressing was set up. The numerical simulations of cylindrical explosive were conducted. The calculated pressures and temperatures in explosives were given. The deformations,pressures and temperatures distribution were analyzed. The calculated results indicated that each surface center of the cylindrical explosive was sunken by isostatic pressing. During the isostatic pressing of cylindrical explosive, the internal temperature of the explosives increases, and the temperature and pressure are not uniform.
Perimeter-Area Relation of Fractal Island
LONG Qi-Wei
1990, 4(4): 259-262 .   doi: 10.11858/gywlxb.1990.04.004
[Abstract](15808) [PDF 1508KB](2371)
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The relationship of perimeter with area (P/A relation) of fractal island is discussed. It is shown that Mandelbrot's fractal relation between Koch perimeter and area does not hold in the island with finite self-similar generations. This might be the reason why the fractal dimension measured with P/A relation varied with the length of yardstick in previous work.
Long-Distance Flight Performances of Spherical Fragments
TAN Duo-Wang, WEN Dian-Ying, ZHANG Zhong-Bin, YU Chuan, XIE Pan-Hai
2002, 16(4): 271-275 .   doi: 10.11858/gywlxb.2002.04.006
[Abstract](14360) [PDF 2450KB](900)
Abstract:
Using two-stage light gas gun and laser technique for velocity easurement, we studied the long-distance flight performances of spherical fragments with different materials and different diameters. The flight distance is 60~120 m, and the initial velocity is 1.2~2.2 km/s. The experimental results show that: (1) the velocity attenuation coefficient of spherical fragment is constant, and (2) the air drag coefficient is slightly affected by the initial velocity of spherical fragment, the air drag coefficient is a linear function of initial velocity.
Design of the Sample Assembly for Ultrasonic Measurement at High Pressure and 300 K in Six-Side Anvil Cell
WANG Qing-Song, WANG Zhi-Gang, BI Yan
2006, 20(3): 331-336 .   doi: 10.11858/gywlxb.2006.03.019
[Abstract](10999) [PDF 411KB](673)
Abstract:
We introduced briefly the principle of design of sample assembly for ultrasonic measurements at high pressure, and designed a new kind of sample assembly to measure the isothermal compression of Al and Cu at 300 K. Ideal quasi-hydrostatic loading was realized, and high-quality ultrasonic signals were obtained under high pressure. It was indicated that the design of sample assembly was reasonable. We analyzed in brief main uncertainty of ultrasonic measurement in six-side anvil cell at 300 K.
Factors Analysis of Debris Cloud's Shape of Hypervelocity Impact
TANG Mi, BAI Jing-Song, LI Ping, ZHANG Zhan-Ji
2007, 21(4): 425-432 .   doi: 10.11858/gywlxb.2007.04.016
[Abstract](13513) [PDF 1599KB](762)
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The numerical simulations of hypervelocity impact of Al-spheres on bumper at normal are carried out using the smoothed particle hydrodynamics (SPH) technique. The simulation results are compared with experimental results, and the simulated hole diameters of bumper and debris cloud are well consistent with experimental results. The effect of impact velocity, bumper thickness, projectile diameter, materials, shape of projectile, interval on produced debris cloud are further analyzed. Regarding the length and diameter as index, orthogonal design method is applied to analyze the primary and secondary relations on the debris cloud's index of the three factors, that is impact velocity, bumper thickness and projectile diameter. The results indicate that bumper thickness is the main influence factor of debris cloud's length while projectile diameter is the main influence factor of debris cloud's diameter.
Application Research on JWL Equation of State of Detonation Products
ZHAO Zheng, TAO Gang, DU Chang-Xing
2009, 23(4): 277-282 .   doi: 10.11858/gywlxb.2009.04.007
[Abstract](15746) [PDF 365KB](930)
Abstract:
By investigating the JWL equation of state of detonation products of condensed explosive, we present a method to determine JWL parameters by fitting. This approach does not require cylinder test and is more economical, secure, convenient and accurate than existing methods. Using this method, four kinds of common explosive, e.g., TNT, C-4, PETN and HMX have been studied. By comparing to the p-V curve of JWL equation of state given by cylinder test, we showed that the fitting has a high precision and meets the need of explosion mechanics application.
Detonation Shock Dynamics Calibration of JB-9014 Explosive at Ambient Temperature
TAN Duo-Wang, FANG Qing, ZHANG Guang-Sheng, HE Zhi
2009, 23(3): 161-166 .   doi: 10.11858/gywlxb.2009.03.001
[Abstract](14348) [PDF 794KB](848)
Abstract:
Detonation shock dynamics (DSD) is an approximation to the reactive Euler equations that allows numerically efficient tracking of curved detonation waves. The DSD parameters are the velocity curvature relation and the boundary angle. A computer code was developed to facilitate the calibration of these parameters for JB-9014 insensitive high explosive using the generalized optics model of DSD. Calibration data were obtained from measurements of the detonation velocities and fronts in JB-9014 rate sticks at ambient temperature, with diameters of 10~30 mm. The steady state detonation velocities and fronts predicted by these DSD parameters are in very good agreement with experiment.
Design and Temperature Calibration for Heater Cell of Split-Sphere High Pressure Apparatus Based on the Hinge-Type Cubic-Anvil Press
CHEN Xiao-Fang, HE Duan-Wei, WANG Fu-Long, ZHANG Jian, LI Yong-Jun, FANG Lei-Ming, LEI Li, KOU Zi-Li
2009, 23(2): 98-104 .   doi: 10.11858/gywlxb.2009.02.004
[Abstract](15020) [PDF 4054KB](866)
Abstract:
A new type of heater cell for the split-sphere high pressure apparatus based on the hinge-type cubic-anvil press was reported. This heating apparatus has the advantages of being simple, low cost, fast temperature rising, good heat insulation, and the temperature signal can be easily extracted. Carbon tube was used as a heating element for side-heating in our experiments. The size of the sample in the cell can reach 3 mm in diameter, and 7 mm in height. The relationship between the heating electric power and cell temperature was calibrated with Pt6%Rh-Pt30%Rt thermocouples under different pressures. The experimental results indicate that the temperature can reach 1 700 ℃ under the oil hydraulic pressure of 40 MPa (cell pressure is about 10 GPa).The temperature can keep stable for more than 2 h under a fixed power.
Shock Wave Physics: The Coming Challenges and Exciting Opportunities in the New Century-Introduction of the 12th International Conference of Shock Compression of Condensed Matter (SCCM-2001)
GONG Zi-Zheng
2002, 16(2): 152-160 .   doi: 10.11858/gywlxb.2002.02.012
[Abstract](14304) [PDF 500KB](892)
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The 12th Biennial International Conference of the APS Topical Group on Shock Compression of Condensed Matter (SCCM-2001) was introduced. Papers presented in SCCM-2001 were surveyed and the recent progresses on shock compression of condensed matter were retrospected. The basic paradigms and the great achievements of the physics and mechanics of condensed matter at high dynamic pressure and stress were surveyed and revaluated. The coming challenges and exciting opportunities of shock wave physics in the 21 century were prospected.
The Constitutive Relationship between High Pressure-High Strain Rate and Low Pressure-High Strain Rate Experiment
CHEN Da-Nian, LIU Guo-Qing, YU Yu-Ying, WANG Huan-Ran, XIE Shu-Gang
2005, 19(3): 193-200 .   doi: 10.11858/gywlxb.2005.03.001
[Abstract](10871) [PDF 416KB](813)
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It is indicated that the constitutive equations at high strain rates proposed by Johnson-Cook(J-C), Zerilli-Armstrong (Z-A) and Bodner-Parton (B-P) collapse the data of flow stress in compression, tension, torsion, and shear into simple curve with the scalar quatities 'effective' stress and 'effective' strain, however, the collapsed data of flow stress did not include the data in the planar shock wave tests. The SCG constitutive equation proposed by Steinberg et al for the planar shock wave tests is discussed, which describes the coupled high pressure and high strain rate effects on the plastic deformation of materials. Basing on the recent experiments at elevated temperatures and high strain rates and the shear strength measurements during shock loading, the flow stress for tungsten at high pressure and high strain rates is estimated with J-C and SCG constitutive equations, respectively. It is concluded that the J-C, Z-A and B-P constitutive equations may not be appropriate to describe the plastic behavior of materials at high pressure and high strain rates, comparing with SCG constitutive equation. It is emphasized that the physical background of the constitutive equation at high pressure and high strain rates is different from that at low pressure and high strain rates.
Phase Evolution of Zr-Based Bulk Metallic Glass Prepared by Shock-Wave Quenching under High Temperature and High Pressure
YANG Chao, CHEN Wei-Ping, ZHAN Zai-Ji, JIANG Jian-Zhong
2007, 21(3): 283-288 .   doi: 10.11858/gywlxb.2007.03.011
[Abstract](14133) [PDF 534KB](733)
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Phase evolution (PH) of Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) prepared by shock-wave quenching has been studied under high-temperature and high-pressure using in situ synchrotron radiation energy-dispersive X-ray diffraction. The results show that the primarily precipitated phase is Zr2Be17 at applied pressures, but the subsequent PH processes are different. The crystallization temperature increases with pressure, but with a sudden drop at about 6.0 GPa. Compared with experimental results of the BMG prepared by water quenching, it can be concluded that crystallization temperature of the BMGs prepared by shock-wave quenching and water quenching all drop at the same pressure region, at which their PHs are different from those of other pressures. The different PHs and the drop of crystallization temperature may be attributed to that the BMG possesses different atomic configuration at different pressures.