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Dynamic response and damage evolution of Zr-based bulk metallic glass under shock loading

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Journal of Materials Science & Technology 2021年第34期93卷 119-127页

作者： Yan Li Xingwang Cheng Zhaolong Ma Xuhai Li Meng Wang National Key Laboratory of Science and Technology on Materials under shock and Impact School of Material Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Science and Technology on shock Waves and Detonation Physics Laboratory Institute of Fluid PhysicsChinese Academy of Engineering PhysicsMianyang 621900.China

Dynamic response and damage evolution of Zr_(70)Cu_(13)Ni_(9.8)Al_(3.6)Nb_(3.4)Y_(0.2) bulk metallic glass(Zr-based BMG)under impact pressure ranging from 4.03 GPa to 27.22 GPa were *** Hugoniot Elastic Limit(HEL)and the spalling Strength(σ_(sp))were measured as 7.09 GPa and 2.28 GPa,and the curve of impact velocity(D)and particle velocity(u)were also *** the strain rate of~10^(5)s^(-1),local crystallization phenomenon was *** increasing the impact pressure,the failure mode of Zr-based BMG changed from spallation to fragmentation caused by the combination of spalling cracks and longitudinal ***-cup structures were also observed in the internal spalling zone via nano-CT *** increasing the impact pressure,the thickness of Zr-based BMG increased after impact and the remelting and cladding layers were also observed on the fracture *** fragments of the specimen were welded after impact due to the high temperature remelting,which causes plastic deformation of Zr-based BMG under shock loading.

关键词： Zr-based bulk metallic glass shock loading Dynamic response Damage evolution

Experimental Study on the Dynamic Mechanical Properties of Reinforced Concrete under shock loading

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Acta Mechanica Solida Sinica 2016年第1期29卷 22-30页

作者： Haifeng Liu Jie Fu Jianguo Ning Department of Civil and Hydraulic Engineering Ningxia University State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

A simple experimental method was introduced to study the mechanical properties of reinforced concrete under shock loading. The one-stage light gas gun was used to test the me- chanical properties of reinforced concrete with different reinforcement ratios under various impact velocities. Three Mn-Cu piezoresistive pressure gauges embedded in the target were used to record the voltage-time signals, from which the stress-strain curves of reinforced concrete were obtained using Lagrangian analysis. Experimental results indicated that the load-bearing capacities of re- inforced concrete increased greatly with the impact velocity and the reinforcement ratio. The peak stress of the shock wave decreased exponentially with the propagation distance.

关键词： reinforced concrete shock loading Lagrangian analysis dynamic mechanical properties

Plasticity and melting characteristics of metal Al with Ti-cluster under shock loading

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Chinese Physics B 2021年第7期30卷 200-208页

作者： Dong-Lin Luan Ya-Bin Wang Guo-Meng Li Lei Yuan Jun Chen School of Mechatronic Engineering Beijing Institute of TechnologyBeijing 100081China System Engineering Research Institute Beijing 100094China Beijing Special Vehicle Research Institute Beijing 100072China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Center for Applied Physics and Technology Peking UniversityBeijing 100871China

Impurity agglomeration has a significant influence on shock response of metal *** this paper,the mechanism of Ti-clusters in metal Al under shock loading is investigated by non-equilibrium molecular dynamics *** results show that the Ti-cluster has obvious effects on the dislocation initiation and melting of bulk ***,the Ti clusters induces the strain concentrate and leads the dislocations to be initiated from the interface of Ti ***,dislocation distribution from the Ti-cluster model results in a formation of a grid-like structure,while the dislocation density is reduced compared with that from the perfect Al ***,the critical shock velocity of dislocation from the Ti-cluster model is lower than from perfect Al ***,it is also found that the temperature near the interface of Ti-cluster is100 K–150 K higher than in the other areas,which means that Ti-cluster interface melts earlier than the bulk area.

关键词： molecular dynamics impurity cluster dislocation shock loading

Simplified design of rock cavern concrete lining to resist shock loading

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Journal of Central South University 2010年第5期17卷 1087-1094页

作者： ZHAO P J LOK T S 殷志强周子龙 Butler Partners Pty Ltd Queensland 4006 Australia Protective Technology Research Centre School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 Singapore School of Resources and Safety Engineering Central South University Changsha 410083 China

A simplified method was proposed for the design of concrete lining in underground rock cavern/tunnel against shock loading. The loading may result from the detonation of explosives on ground surface or ground penetration projectiles exploding adjacent to the cavern/tunnel. The resulting problem necessitates the solution of the dynamics of a beam loaded by a transient pressure uniformly distributed over the span. According to mechanical characteristics of the system with rock bolt and shotcrete, a dynamic support design method based on equivalent single degree of freedom （SDOF） was put forward. The SDOF method was applied to obtaining the maximum displacement at the mid-span of the beam, which is often the controlling factor in the blast-resistant design. In the formulation of the problem, the proposed method combines the phenomena of spalling and structural dynamics theory. An example is provided to demonstrate the applicability of this simplified method.

关键词： tunnel lining design shock loading dynamic response rock cavern

Dynamic strength behavior of a Zr-based bulk metallic glass under shock loading

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Chinese Physics B 2015年第6期24卷 461-465页

作者：俞宇颖习锋戴诚达蔡灵仓谭叶李雪梅吴强谭华 Laboratory for shock Wave and Detonation Physics Research Institute of Fluid PhysicsChinese Academy of Engineering Physics

Dynamic strength behavior of Zr51Ti5NiloCu25A19 bulk metallic glass （BMG） up to 66 GPa was investigated in a series of plate impact shock-release and shock-reload experiments. Particle velocity profiles measured at the sample/LiF window interface were used to estimate the shear stress, shear modulus, and yield stress in shocked BMG. Beyond confirm- ing the previously reported strain-softening of shear stress during the shock loading process for BMGs, it is also shown that the softened Zr-BMG still has a high shear modulus and can support large yield stress when released or reloaded from the shocked state, and both the shear modulus and the yield stress appear as strain-hardening behaviors. The work provides a much clearer picture of the strength behavior of BMGs under shock loading, which is useful to comprehensively understand the plastic deformation mechanisms of BMGs.

关键词： shock loading dynamic strength bulk metallic glass

Phase Transformations in ZrO_2 after shock loading

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Journal of Materials Science & Technology 1993年第1期9卷 32-36页

作者： Sergey N.Kulkov Alexander G.Melnikov Institute of Strength Physics and Materials Science.

The effects of shock loading on the morphology,grain growth during heating and phase transforma- tion of ZrO_2 have been *** is shown that shock loading may be efficiently used to modify submicron ceramic powders with nanocrystalline *** shock loading,the critical diameter of ZrO_2 particles transformed from tetragonal to monoclinic decreased due to stored strain energy. Annealing of powders resulted in reversible transformation to the tetragonal without considerable grain growth up to 1200℃.

关键词： submicron ceramics nanocrystalline shock loading phase transformation

Effect of Salinity Variations on the Performance of Activated Sludge System

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Biomedical and Environmental Sciences 2005年第1期18卷 5-8页

作者： JIAN-LONGWANG XIN-MINZHAN YE-CHENGFENG YIQIAN LaboratoryofEnvironmentalTechnology INETTsinghuaUniversityBeijing100084China StateKeyJointLaboratoryofEnvironmentSimulationandPollutionControl TsinghuaUniversityBeijing100084China

To investigate the influence of salinity variations on the performance of activated sludge systems, treating domestic wastewater. Methods The completely mixed reactor was used and operated in a batch-wise mode. The activated sludge taken from the Gaobeidian Wastewater Treatment Plant was used as a seeding sludge. Total organic carbon (TOC), oxygen uptake rate (OUR) and suspended solids (SS) were used as parameters to characterize the performance of the treatment systems. TOC was measured using a TOC-analyzer (TOC-5000, Japan). The OUR value was measured with a dissolved oxygen meter (YSI model-58). SS was measured gravimetrically. Results The TOC removal efficiency and the OUR value of activated sludge were not deteriorated when the NaCl shock concentration was less than 0.5 g/L. However, when the NaCl shock concentrations were up to 10g/L and 20 g/L, the OUR of activated sludge was reduced by 35% and TOC removal efficiency was dropped by 30%, compared with the control experiment without NaCl shock loading. Conclusion The effect of NaCl shock loading on the activated sludge wastewater treatment system is dependant upon the NaCl concentrations and the degree of influence can be inferred through the change of substrate utilization rate at different shock NaCl loadings.

关键词： Activated sludge Saline wastewater NaCl shock loading TOC OUR

Investigation on the shock Response of Vitreous Carbon

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Journal of Beijing Institute of Technology 2002年第1期11卷 75-80页

作者：吴成北京理工大学机电工程学院北京100081

The dynamic response of vitreous carbon to uniaxial strain loading has been investigated by means of the plate impact experiments. The two x cut shorted quartz gauges assembled with impactor and target were used to obtain the wave speeds in material and the stress histories at the sample gauge interface. The wave speed and stress histories were analyzed to determine the peak state in the sample. For compressive stress up to 4 0 GPa, the wave profiles were observed to be simple and steady, the uniaxial strain response is essentially nonlinear elastic, and no inelastic deformation has been found. All the experiment results indicate that the Hugoniot curve of vitreous carbon is concave downward just like that of fused silicon. There is no shock wave but the compressed wave propagating in the impacted samples.

关键词： uniaxial strain shock loading vitreous carbon Hugoniot elastic limit shock compressive wave

Investigations of shock-Induced Dislocation Plasticity by a Multiscale Coarse Grained Model at Submicron Scale

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Investigations of Shock-Induced Dislocation Plasticity by a ...