Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Display Method:
2022, 36(5)  
2022, 36(5): 1-2.  
Physical Property and Structure
Criteria of Mechanical Stability of Seven Crystal Systems and Its Application: Taking Silica as an Example
GAO Juan, LIU Qijun, JIANG Chenglu, FAN Daihe, ZHANG Miao, LIU Fusheng, TANG Bin
2022, 36(5): 051101.   doi: 10.11858/gywlxb.20220575

According to the positive definiteness of the quadratic type, and based on the mechanical stability criteria derived by Mouhat and Coudert, the mechanical stability criteria of monoclinic and triclinic crystal systems are supplemented. The mechanical stability criteria of the seven crystal systems are given. Based on the density functional theory of the first principle method, the elastic constants of nine kinds of SiO2 belonging to different crystal systems are calculated. Combined with the mechanical stability criteria, the stabilities of SiO2 in different space groups, including cubic P213, hexagonal P63/mmc, trigonal P3121 and $R\overline 3 $, tetragonal P41212 and $I\overline 4 $, orthorhombic Pbcn, monoclinic P21/c, and triclinic $P\bar 1$, are determined. The calculated results show that the nine types of SiO2 are all mechanically stable at 0 GPa.

High-Pressure Raman Spectroscopy of hcp Metals
LIU Jingyi, TAO Yu, FAN Chunmei, WU Binbin, LEI Li
2022, 36(5): 051102.   doi: 10.11858/gywlxb.20220522

The lattice dynamics behavior of materials under high pressure can be studied by high-pressure Raman spectroscopy. However, Raman spectroscopic signal of metal samples at high pressure is difficult to obtain due to the fluorescence of the diamond in diamond anvil cell (DAC) and the strong reflection of the samples. In this work, we use DAC inclination scattering method to mitigate background noise. As a consequence, Raman spectroscopic signal of the hcp metal samples (Be, Re, Os) under high pressure have been achieved. In the case of Be, the pressure dependence of elastic constant C44 is obtained by measuring the shear Raman mode E2g at pressure up to 73 GPa. The proposed high-pressure Raman spectroscopy technique provides a new method to study bonding state, electronic structure, and phonon-electron coupling effects of metallic materials under high pressure.

Crystal Structure and Thermal Properties of Polypropylene Prepared by Variable Speed Pressurization
XU Mingkun, LIN Jiaxiang, ZHANG Xiaolin, LI Zhenyin, SHAO Chunguang
2022, 36(5): 051103.   doi: 10.11858/gywlxb.20220570

In the high-pressure molding process of polymers, the pressure, pressurization rate and molecular weight of the polymers will affect the final crystalline structure of the products. Studying the relationship between different high-pressure processing methods and the crystalline structure of isotactic polypropylene (iPP) is helpful to deeply understand the influence of high-pressure molding process on the crystallization behavior of polymers. In this paper, wide-angle X-ray diffraction and differential scanning calorimetry were used to study the crystallization behavior and thermal properties of two kinds of iPP with different molecular weights at different pressurization rates and pressures. The results show that pressure is a key factor in determining the formation of mesophase iPP. The complete mesophase iPP can be prepared under sufficient pressure. Under enough pressure, the higher the pressurization rate, the easier to form mesophase iPP, ortherwise, to form γ-phase iPP. The higher the molecular weight, the higher pressure required for the preparation of mesophase iPP, and the greater the required critical pressurization rate. The thermal property analysis of the products shows that the thermal properties of the mesophase products obtained under different conditions are basically the same, but the crystal perfection of the γ-phase iPP is related to the pressurized condition.

Reciprocating Phase Transitions Behavior of Germanium under High Pressure
YUAN Qin, LI Shuaiqi, ZHOU Li, HE Duanwei
2022, 36(5): 051104.   doi: 10.11858/gywlxb.20220578

Based on a two-stage multi anvil apparatus, with diamond anvil cell device, combined with the high-pressurein situX-ray diffraction (XRD) technology of Beijing Synchrotron Radiation Light Source, the phase transitions and grain size variation behaviors of germanium under high pressure were systematically investigated. It is found that the reciprocating phase transitions indeed have obvious effects on the grain refinement of germanium. At the same time, the amorphous regions are found in the bulk samples that have undergone five times reciprocating phase transitions, which provides a new way for the preparation of nanostructured and amorphous materials.

Theory and Calculation
Numerical Study on Wave Effect of the Frictional Interface
LIU Yonggui, HUI Mengmeng, SHEN Lingyan
2022, 36(5): 052301.   doi: 10.11858/gywlxb.20220513

Interface friction is a common natural phenomenon. Based on the micro-contact fracture mechanism of friction, a two-dimensional interface friction model including a triangular micro bulge is established with linear elastic constitutive relationship and D-P failure criterion. The early dynamic behavior of the interface under transient loading is numerically calculated and analyzed by the finite element simulation method. The research shows that in the micro process of loading, there exist significant stress fluctuations and fine structure characteristics at frictional interfaces. The evolution of the wavefront in the near region of the interface has symmetrical diffusion. The interaction of the incoming stress disturbance and the micro bulge will induce the fracture of the bulge, resulting in a three-wave profile centered on the fracture surface: longitudinal wave, transverse wave, and interface wave. A new interesting phenomenon is that at the moment of loading, a micro stress disturbance is generated synchronously from the interface and propagates to the substrate in the form of longitudinal waves. More comparative examples and analysis show that the mechanism of this disturbance is related to the overall gravity micro-adjustment acting on the interface. This work reveals the early wave effect of interface friction and its micro fracture mechanism, which is expected to provide an effective way for earthquake prediction and to advance the earthquake prediction time.

Dynamic Response of Matter
Response Characteristics of Spring-Mass System under Impact of Momentum Ball
MO Xiaolei, LIN Yuliang, LI Yugang
2022, 36(5): 054101.   doi: 10.11858/gywlxb.20220566

Impulse is an important power parameter of explosive air shock wave, and the momentum-block test method is one of the ways to measure the impulse. This paper attempts to convert the momentum of the momentum-ball into the quantitative compression displacement of the spring by investigating the impact response characteristics of spring-mass system. Four different momentum-balls impact tests, such as polyformaldehyde, polytetrafluoron, aluminum and steel, were conducted to obtain the spring-mass compression response characteristics and momentum/energy conversion efficiency. The results show that the maximum compression displacement of the spring is linearly related to the loading velocity of the momentum-ball. The polyformaldehyde momentum-ball spring coupling system shows the most stable properties, which is suitable for the transfer carrier of shock wave impulse measurement. This work can provide a new method for shock wave measurement.

Effect of Aging Temperature on Dynamic Mechanical Properties of TB8 Titanium Alloy
CHEN Wen, GUO Baoqiao, GUO Yansong, LUAN Kedi, RAN Chun, CHEN Pengwan
2022, 36(5): 054102.   doi: 10.11858/gywlxb.20220528

TB8 (Ti-15Mo-2.7Nb-3Al-0.2Si) is a metastable β titanium alloy, which plays an important role in the aerospace field. Microstructure, strain and strain rate are three important factors affecting mechanical properties of TB8 titanium alloy. Based on a universal material testing machine and a split Hopkinson pressure bar (SHPB) device, the effect of solution and aging heat treatment process on mechanical properties of TB8 titanium alloy was studied. Optical microscope (OM) and scanning electron microscope (SEM) were used to characterize the microstructure and section morphology of the specimens before and after deformation. The results show that short strip α phase precipitates inside the alloy after solution and aging treatment, and the size and quantity of secondary phase increase with aging temperature increasing. Under different loading conditions, the strain rate strengthening effect of TB8 titanium alloy before and after heat treatment is obvious, but the strain strengthening effect is not obvious under dynamic loading condition. With the increase of aging temperature, the yield strength of the alloy decreases and the plasticity increases. The failure mode of specimens under dynamic loading is typical shear failure. Adiabatic shear band is the precursor of crack formation and specimen failure.

Dynamic Response and Damage Failure Behavior of TC4 Titanium Alloy Hollow Fan Blade
ZHANG Yongqiang, JIA Lin
2022, 36(5): 054103.   doi: 10.11858/gywlxb.20220546

Aero-engine is a high probability and high-risk component of bird strike events, which is of great significance to the study of bird strike resistance of fan blades. In this paper, based on the three-dimensional digital image correlation (DIC) in-situ strain measurement method, the static bird strike tests of TC4 titanium alloy hollow structure fan blades at different heights are carried out. In addition, a simulation model is established based on Johnson-Cook dynamic constitutive model and damage failure theory to better verify and describe the dynamic deformation response process and failure situation of aero-engine fan blades during bird strikes. It is found that the variation of bird strike velocity mainly affects the magnitude of blade deformation, but does not cause the change of blade characteristic mode. In the bird strike process, the middle root is a significant area of stress/strain localization, which is more prone to damage failure. It is found that with the increase of bird impact position, the critical bird impact velocity corresponding to the failure of the hollow fan blade at the blade root increases gradually, and the bird impact resistance of the whole structure is better. This experiment and the corresponding simulation study provide a certain reference for the anti-bird impact design of the TC4 titanium alloy hollow structure fan blade.

Topological Optimization and Dynamic Response of Periodic Porous Sandwich Structure under Impact Load
LIAO Fang, LI Shiqiang, WU Guiying
2022, 36(5): 054201.   doi: 10.11858/gywlxb.20220560

In this study, under the frame of equivalent static loads (ESL) method structural optimization and based on hard-kill bi-directional evolutionary structural optimization (hard-kill BESO), the topological optimization method for periodic porous sandwich structure under impact load was carried out. The commercial software ABAQUS was used to investigate the deformation patterns of the optimized periodic sandwich structure and the sandwich structures with trapezoidal, rectangular and random Voronoi cores under the impact load imposed by a rigid body with an initial velocity of 100 m/s. In the early stage of load, the upper half of the core layer of the optimized periodic sandwich structure is completely compressed and the energy absorption is higher than the other three structures. However, the total energy absorption of the optimal sandwich structure is slightly less than the other three due to the small plastic deformation at the end stage of load. To study the capabilities of the topologically optimized structure under different load conditions, the energy absorption performance of the four sandwich structures subjected to the rigid body impact loads at different velocities and three impulse loads were compared. After comprehensively considering the deflection at the centers of top and bottom panels, the specific energy absorption, the ratio of energy absorption of core layer, as well as the mean impact load, it shows that the optimized sandwich periodic structure performs higher energy absorption capability and resistance under the rigid body impact. The specific energy absorption of the optimal sandwich structure is less than the sandwich structure with rectangular core under rectangular impulse, losing advantages of the structural optimization. It indicates that the optimization design obtained under a single load condition cannot get the best performance for any load condition, and further research is required for different load conditions.

Dynamic Model of Clamped Elastoplastic Circular Plate under Air Blast Loading
WU Di, MI Guo, GUO Xianghua, ZHANG Qingming
2022, 36(5): 054202.   doi: 10.11858/gywlxb.20220525

Based on equivalent single degree-of-freedom (SDOF) theory, a dynamic model of clamped elastoplastic circular plate under near air blast loading is established by considering the bending moment and the membrane force during the deformation process, and the whole process containing loading and unloading for circular plate is described. The finite element model is established using test parameters in the literature, and the dynamic response of clamped circular plate under air blast loading is analyzed by finite element simulation. After comparing the calculation results of the dynamic model and the finite element simulation results, the accuracy of the calculation results of the dynamic model is verified. The results show that the theoretical calculation results are in good agreement with the test results and the finite element simulation results. The proposed dynamic model can be applied to predict the large deformation of clamped circular plate under near air blast loading, and provides technical support for blast resistant structure.

Numerical Simulation of Crack Propagation and Damage Behavior of Glass Plates under Impact Loading
WANG Mufei, LI Zhiqiang
2022, 36(5): 054203.   doi: 10.11858/gywlxb.20220558

Crack initiation and propagation is a long-standing difficult problem in solid mechanics, especially for elastic-brittle material. To explore the damage and crack propagation behavior of glass plates under impact loading, the element deletion, discontinuous Galerkin peridynamic (DG-PD), and meshless peridynamic (M-PD) methods are used to conduct numerical simulations, respectively. The JH-2 material model, and the maximum principal stress and maximum principal strain failure criteria are adopted in the element deletion method. The node separation operation and the critical energy release rate criterion are used in the DG-PD method. In the M-PD method, a self-programmed particle discretization method is utilized along with an appropriate computational domain, and a critical elongation criterion is imposed. The simulation results show that: (1) the element deletion method can roughly simulate the damage morphology of glass under impact loading, but it is insufficient in capturing crack bifurcation and penetration. (2) In the DG-PD method, circumferential cracks and radial cracks are observed, and the cracks are of high symmetry. In addition, there are a lot of glass fragments splashing at the impact point and the frame. (3) Radial cracks and circumferential cracks can be captured in the M-PD method, and the symmetry of the cracks is good. The size of horizon and the impact velocity show great influence on the dynamic responses of the glass plates. As far as the damage form is concerned, the M-PD method and the DG-PD method yield consistent results.

Numerical Analysis of Dynamic Mechanical Characteristics of Brazilian Splitting of Coal-Rock Combination Bodies
MA Sizhou, LIU Kewei, GUO Tengfei, HUANG Xiaohui, ZHOU Zhanxing
2022, 36(5): 054204.   doi: 10.11858/gywlxb.20220589

In order to investigate the dynamic mechanical characteristics of coal-rock composite engineering body under impact load, the basic mechanical parameters of pure coal and pure rock were obtained by laboratory tests for determining the parameters of HJC model. Based on the validity verification of the material model, LS-DYNA was employed to study the stress wave propagation features, failure process and failure characteristics of coal-rock combination bodies in dynamic splitting process considering the effects of impact loads, impact directions and loading angles. The results showed that: (1) the stress wave shapes of R-C and C-R samples are almost the same for different impact directions, but the stress amplitudes are slightly different. The comparison results showed that the incident wave amplitudes are similar, but for R-C samples, the amplitude of reflected wave is larger while that is smaller of transmitted wave. The difference gradually decreases with the increasing impact loads. (2) Under the action of different impact loads, the coal part is mainly damaged in the process of splitting, and the cracks generally appear in the coal part far from the interface, while the rock part commonly is damaged at the near side of the interface. (3) The failure modes of C-R and R-C samples are similar and mainly tensile and shear when the impact load is relatively low. The damage degree of the combination body is aggravated with increasing load, and the difference of failure modes becomes more obvious. (4) A method using the number of failure elements as an evaluation index is proposed to quantitatively analyze the breakage degree of the combination bodies. According to the numerical simulation results, the combination body damaged most seriously for the loading angle of 45°.

Crashworthiness Optimization of Horsetail-Bionic Thin-Walled Structures
LIU Feiming, LEI Jianyin, QIAO Li, LIU Zhifang
2022, 36(5): 054205.   doi: 10.11858/gywlxb.20220516

Numerical model of horsetail-bionic thin-walled structure (HBTS) under the lateral impact was constructed using ABAQUS. The effects of wall thickness, inner diameter and number of ribs on the crashworthiness performance and deformation modes were analyzed. The results indicate that the specific energy absorption and peak load of HBTS can be significantly enhanced with the increase of the number of ribs and the overall wall thickness. The changes in the wall thickness of each part significantly affects its deformation mode and crashworthiness performance. Based on the above results, the optimization software modeFRONTIER and the finite element analysis software ABAQUS were integrated to explore the influence of five design parameters, in terms of wall thickness, number of ribs, inner diameter and so on. Finite element models were uniformly distributed on the design space through parametric modeling method, hence the Kriging surrogate models for the specific energy absorption and peak load were established. Then, Pareto front was obtained using Kriging surrogate model-based multi-objective optimization method for the specific energy absorption maximization and peak load minimization simultaneously in one model. Finally, the distribution of each HBTS’s design parameters on Pareto front was analyzed and the optimization results were verified. The method is expected to provide new thoughts for the optimization design of the thin-walled structure.

High Pressure Applications
Influence of Coupled Macroscopic Deviation of Shaped Charge on Lateral Displacement of Jet
NIE Yuan, LIANG Bin, YUAN Xiaoya, LIU Chuang, LI Yi
2022, 36(5): 055101.   doi: 10.11858/gywlxb.20220511

Macroscopic deviation of shaped charge is one of the reasons for lateral deviation of induced jet. In order to study the influence of multiple coupled macro deviations on the lateral deviation of jet, theoretical model considering the effects of the coaxiality deviation, the liner thickness deviation and the position deviation on the lateral deflection of the jet was deduced according to the jet forming theory. The numerical simulations of the jet forming process for the shaped charge containing multiple macroscopic deviations were carried out. The results show that the coaxiality deviation and the position deviation both cause the jet to form a quadratic curve, and the liner thickness deviation makes the jet deflect, but still maintain a straight shape. For the cases of multiple macroscopic deviations coupling, the lateral displacement of the jet is approximately the vector sum of the displacements caused by each single factor. The results provide a reference for improving the stability of shaped charge.

Influence of Flame Characteristics on Fast Cook-off
XIAO You, ZHI Xiaoqi, WANG Qi, YU Yongli, FAN Xinghua
2022, 36(5): 055201.   doi: 10.11858/gywlxb.20220557

In order to study the influence of flame characteristics on cook-off bomb in pool fire under the condition of fast cook-off, a fast cook-off model of pool fire was established, and the heat transfer characteristics of the cook-off bomb were obtained, then the influences of the placement height of the cook-off bomb and the size of the oil pool on the flame characteristics during the burning process were analyzed. The results show that with the increasing placement height of the bomb, the highest temperature region of the bomb surface shifts from the upper surface to the lower surface, and the peak radiation heat flux shifts from the top to the bottom of the bomb. With the increasing size of the oil pool, the surface temperature of the bomb becomes more uniform, the heat flux absorbed by the bomb increases, and the surface temperature of the bomb increases. Therefore, in the fast cook-off test, both the placement height of the bomb and the size of the oil pool affect the flame characteristics, and then the fast cook-off characteristics of the bomb.

Cook-off Test and Numerical Simulation of HMX-Based Cast Explosive Containing AP
LIU Runze, WANG Xinjie, LIU Ruifeng, DUAN Zhuoping, HUANG Fenglei
2022, 36(5): 055202.   doi: 10.11858/gywlxb.20220538

In order to study the response characteristics of a new HMX-based cast explosive GOLA-1 (HMX-aluminum-ammonium perchlorate (AP)-binder (Kel-F)) under thermal stimulation, the cook-off tests with heating rates of 1.0 and 1.5 K/min were conducted, and the information such as the temperature rise of the explosive center point and the ignition time was obtained. On that basis, and combined with numerical simulation of cook-off, the ignition position and temperature of explosives were predicted. The numerical simulation is in good agreement with the experimental results. The ignition time deviations of GOLA-1 explosive at heating rates of 1.0 and 1.5 K/min are 1.3% and 1.7%, respectively, indicating that the established simulation model is reasonable. On above basis, numerical simulations at different heating rates were carried out. The results show that when the heating rate decreased to 0.4 K/min, the ignition position moved from the annular area at the bottom edge of the charge to the lower part of the central axis of the charge column. As the heating rate continued to decrease, the ignition position gradually moved to the upper part of the charge, while the heating rate had little effect on the ignition temperature.

Surface Vibration Cavity Effect of Underpass Blasting in Urban Metro Liaison Channel
DONG Hefei, ZHU Bin, JIANG Nan, YANG Yumin
2022, 36(5): 055301.   doi: 10.11858/gywlxb.20220553

The study of surface vibration attenuation law of urban underground engineering blasting construction is of great significance for the protection of adjacent buildings. This paper takes the Wuhan Metro Line 8 Phase Ⅱ liaison channel blasting excavation project as an example and uses a combination of field monitoring and ANSYS/LS-DYNA 3D finite element numerical simulation to analyze the characteristics of surface vibration hollow effect under the liaison channel blasting excavation and predict its attenuation law. The results indicate that where the surface vibration speed is significantly greater than the unexcavated area, there is a “cavity effect”; with the increase of the longitudinal distance between the mass point and the source of the explosion, the cavity effect amplification coefficient increases rapidly until the extreme value and then slowly decreases. Along both sides of the channel with the increase in distance, the amplification coefficient decreases, the effect of the cavity effect is weakened, at a distance of 8 m from the source (6 m behind the palm surface) to reach the maximum, 2−8 m from the source of the cavity effect should focus on vibration monitoring within the surface area. The excavation area with the blasting conditions is related to the coefficient of 58.52, and vibration attenuation coefficient of 1.43, while the unexcavated area of 152.09, and vibration attenuation coefficient of 1.74, the absorption coefficient of the layer media are 0.019, 0.023, respectively.

Water Inrush Risk Prediction of Karst Tunnel Based on IAHP-Fuzzy Method
LI Lu, QIN Bendong, GUO Jiaqi, HUANG Xin, TIAN Yongchao
2022, 36(5): 055302.   doi: 10.11858/gywlxb.20220536

Water and mud inrush is one of the main engineering disasters in the construction stage of karst tunnel, so it is necessary to predict its potential risk level. Taking Yesanguan tunnel of Yiwan railway as the engineering background, the factors affecting the water inrush risk of the tunnel are summed up as engineering geological conditions, hydrogeological conditions and rock mass quality conditions by the literature survey method, and the corresponding evaluation index system is established. The interval judgment matrix of factors at each level is formed to determine the index weight, and the interval analytic hierarchy process (IAHP)-Fuzzy method is used to realize the classification of water inrush risk in karst tunnels. The analytic hierarchy process model and risk classification system of water and mud inrush in tunnels are formed by combining 3 first-level indexes and 11 second-level indexes. The index weights are determined by IAHP. The calculation results show that water pressure characteristics account for the highest proportion in all indexes, and high water pressure is the most direct cause of water inrush in Yesanguan tunnel. Through the verification calculation, the risk of water inrush in the tunnel is weak when the water pressure is 0.1 MPa, which effectively reduces the risk of water inrush. It is suggested to take active protective measures such as pre-grouting reinforcement to reduce the water pressure and guide the actual construction. The verification further proves the feasibility of the model.

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](13330) [PDF 8643KB](2176)
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](9355) [PDF 2836KB](1941)
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](15128) [PDF 6073KB](2591)
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](15722) [PDF 1350KB](1069)
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](13807) [PDF 12118KB](930)
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](8095) [PDF 1765KB](254)
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](16785) [PDF 689KB](941)
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.
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](10458) [PDF 402KB](746)
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](13346) [PDF 1180KB](787)
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.
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](10587) [FullText HTML](4552) [PDF 2527KB](4552)

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.

Perimeter-Area Relation of Fractal Island
1990, 4(4): 259-262 .   doi: 10.11858/gywlxb.1990.04.004
[Abstract](15435) [PDF 1508KB](2320)
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](13981) [PDF 2450KB](849)
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.
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](13098) [PDF 1599KB](692)
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.
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](13954) [PDF 500KB](836)
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.
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](14043) [PDF 794KB](786)
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 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](10621) [PDF 411KB](612)
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.
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](14509) [PDF 4054KB](758)
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.
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](10552) [PDF 416KB](735)
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](13771) [PDF 534KB](684)
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.
Explosive Shock Synthesis of Wurtzite Type Boron Nitride
TAN Hua, HAN Jun-Wan, WANG Xiao-Jiang, SU Lin-Xiang, LIU Li, LIU Jiang, CUI Ling
1991, 5(4): 241-253 .   doi: 10.11858/gywlxb.1991.04.001
[Abstract](11781) [PDF 4689KB](2131)
Reported in the paper are techniques of wurtzite type boron nitride (wBN) synthesis from graphite type BN (gBN) by means of shock compressions created via explosive detonation. Recovered samples after shock processing are treated with molten alkalis and hydrochloric acid. Despite that the domestic gBN materials we used are far inferior, both in the crystallinities and particle sizes, to those used in foreign countries for the purpose of shock synthesis of wBN, the yield of our wBN reaches 11 to 12 g per shot, with a convertion ratio over 50%; X-ray diffraction and x-ray fluorescence spectrometry analyses reveal that the total impurity content of this chemically extracted wurtzite type boron nitride product is less than 0.5%. Four different starting gBN from different manufacturers were used in the experiments to synthesis wBN under the same conditions of shock compressions. It is found that the yield of wBN is closely related to the crystallinity of the starting gBN materials. Specific area measurements and XRD analysis indicate that our wBN is a polycrystal super-fine powder material with average particle size of 0.1 m, which consists of many primary crystallites of 17.5 nm in dimension. Thermal stability of our wBN powder is characterized by the emergence of an exothermic peak in the atmospheric gas condition from DTA analysis. Initial temperature of this exothermic reaction is about 1 055 K and peak temperature 1 238 K.

Hosted by:Topical Communitte of High Pressure,
Chinese Physical Society

Sponsored by:Institute of Fluid Physics,CAEP

Editor-in-Chief:ZOU Guangtian