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Haifu Wang - One of the best experts on this subject based on the ideXlab platform.
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penetration behavior of high density reactive material liner Shaped Charge
Materials, 2019Co-Authors: Huanguo Guo, Haifu Wang, Jianwen Xie, Yuanfeng ZhengAbstract:The traditional polytetrafluoroethylene (PTFE)/Al reactive material liner Shaped Charge generally produces insufficient penetration depth, although it enlarges the penetration hole diameter by chemical energy release inside the penetration crater. As such, a novel high-density reactive material liner based on the PTFE matrix was fabricated, and the corresponding penetration performance was investigated. Firstly, the PTFE/W/Cu/Pb high-density reactive material liner was fabricated via a cold pressing/sintering process. Then, jet formation and penetration behaviors at different standoffs were studied by pulse X-ray and static experiments, respectively. The X-ray results showed that the PTFE/W/Cu/Pb high-density reactive material liner forms an excellent reactive jet penetrator, and the static experimental results demonstrated that the penetration depth of this high-density reactive jet increased firstly and then decreased by increasing the standoff. When the standoff was 1.5 CD (Charge diameter), the penetration depth of this reactive jet reached 2.82 CD, which was significantly higher than that of the traditional PTFE/Al reactive jet. Moreover, compared with the conventional metal copper jet penetrating steel plates, the entrance hole diameter caused by this high-density reactive jet improved 29.2% at the same standoff. Lastly, the chemical reaction characteristics of PTFE/W/Cu/Pb reactive materials were analyzed, and a semi-empirical penetration model of the high-density reactive jet was established based on the quasi-steady ideal incompressible fluid dynamics theory.
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penetration behavior of reactive liner Shaped Charge jet impacting thick steel plates
International Journal of Impact Engineering, 2019Co-Authors: Huanguo Guo, Yuanfeng Zheng, Haifu WangAbstract:Abstract Reactive liner Shaped Charge jet (RLSCJ) penetrates thick steel plate by experiments and model analysis combined. The experimental reactive material liners with a density of about 2.3 g/cm3, composed of mass matched ratios of Al/PTFE powders, are consolidated by a cold pressing/sintering process. Four standoffs of 0.5, 1.0, 1.5, and 2.0 CD (Charge diameter) are selected to conduct the penetration experiments. The experimental results show that, compared with traditional metal liner Shaped Charge jet against thick steel plates, a relative larger hole diameter but lower depth accompanying with fragmentation effects of penetrating steel plates are produced by RLSCJ. To understand this penetration behavior of reactive jet, an analytical model is developed to discuss the influence of initiation delay time of reactive jet and standoff on penetration depth. Analysis shows that the penetration depth strongly depends on initiation delay time of reactive jet. With increasing the initiation delay time, the penetration depth increases significantly, showing a good agreement with the experiments. Moreover, to further understand the fragmentation mechanism effect of the thick steel plates, the effective mass of reactive jet inside the penetrating hole and its deflagration-induced structural damage effect are analyzed theoretically. Prediction results fit well with the experiments, including crack generation and propagation in the thick steel plates, and the number of fragments.
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demolition mechanism and behavior of Shaped Charge with reactive liner
Propellants Explosives Pyrotechnics, 2016Co-Authors: Jianguang Xiao, Xuepeng Zhang, Yongzhi Wang, Haifu WangAbstract:The application of reactive materials on Shaped Charge liners has received much attention. Herein, the demolition mechanism and behavior of reactive materials based Shaped Charge liner are investigated by experiment, numerical simulation, and theoretical analysis. Three reactive Shaped Charge liners, composed of a mixture of Al/PTFE (26.5/73.5 wt-%) powders, are fabricated by pressing and sintering. The damage effects of the multi-layered target against reactive materials based Shaped Charge are investigated. The results show that the reactive liners create excellent collateral damage due to the release of chemical energy contained in reactive materials. An Eulerian computational model is developed to investigate penetration behavior of the reactive jet formed by Shaped Charge liner. In addition, a theoretical model based on cavity expansion is derived to predict the initiated location of reactive materials. Comprehensive analysis indicates that the TNT equivalence factor for these powder mixtures used in this work is 3.41–7.77 and that the self-delay time is about 0.8 ms. This work will provide guidance and reference for the design of reactive Shaped Charge liner.
L.e. Murr - One of the best experts on this subject based on the ideXlab platform.
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Dynamic Recrystallization: The Dynamic Deformation Regime
Metallurgical and Materials Transactions A, 2007Co-Authors: L.e. Murr, C. PizañaAbstract:Severe plastic deformation (PD), especially involving high strain rates (>10^3 s^–1), occurs through solid-state flow, which is accommodated by dynamic recrystallization (DRX), either in a continuous or discontinuous mode. This flow can be localized in shear instability zones (or adiabatic shear bands (ASBs)) with dimensions smaller than 5 μ , or can include large volumes with flow zone dimensions exceeding centimeters. This article illustrates these microstructural features using optical and electron metallography to examine a host of dynamic deformation examples: Shaped Charge jet formation, high-velocity and hypervelocity impact crater formation, rod penetration into thick targets (which includes rod and target DRX flow and mixing), large projectile-induced target plug formation and failure, explosive welding, and friction-stir welding and processing. The DRX is shown to be a universal mechanism that accommodates solid-state flow in extreme (or severe) PD regimes.
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Adiabatic shear bands and examples of their role in severe plastic deformation
Journal of Materials Science, 2002Co-Authors: L.e. Murr, E. A. Trillo, S. Pappu, C. KennedyAbstract:The accommodation of severe plastic deformation in impact crater formation, ballistic rod flow and penetration in thick targets, Shaped Charge formation, and a variety of friction-stir welding and processing is shown to occur by microstructure refinement, particularly dynamic recrystallization in the development of localized or overlapping adiabatic shear bands. Optical metallography and transmission electron microscopy observations of solid-state flow in adiabatic shear zones are compared to illustrate these mechanisms which can often involve intermixed microstructural regimes composed of recovery, recrystallization, and grain growth phenomena.
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comparison of jetting related microstructures associated with hypervelocity impact crater formation in copper targets and copper Shaped Charges
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1997Co-Authors: L.e. Murr, C S Niou, E P Garcia, E Ferreyra, T J M Rivas, J C SanchezAbstract:Abstract Shaped Charge jet and slug formation is characterized prominently by dynamic recrystallization which may occur in deformation-recrystallization cycles, providing a mechanism for extreme plastic flow in jetting. There was no evidence for melting or melt-related phenomena. Hypervelocity impact crater development is also dominated by dynamic recrystallization in a narrow flow zone where target material is jetted into the crater rim. The crater rim can particulate by velocity gradients along the jetting rim just like the Shaped Charge jet. Like the Shaped Charge, there was no significant melt phenomenon associated with the cratering process, and extreme plastic, high-strain-rate flow occurs in the solid state. Microbands are created in a zone removed from the crater wall in copper targets in response to hypervelocity impact which, like deformation twins, are coincident with the trace of primary 111 planes. Their density and extent increase with both impact velocity and grain size. Neither microbands nor deformation twins are observed in recovered Shaped Charge slug and jet fragments.
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novel deformation processes and microstructures involving ballistic penetrator formation and hypervelocity impact and penetration phenomena
Materials Characterization, 1996Co-Authors: L.e. Murr, C. Kennedy, E P Garcia, E Ferreyra, Javier Sanchez, T S Pappu, W Huang, J M Rivas, A Ayala, C S NiouAbstract:Abstract Light metallography and transmission electron microscopy techniques affording unique observations of microstructural issues in connection with a related set of novel, high-strainrate deformation processes provide some fundamental insight into the following areas: shock-wave-induced twinning, explosive welding, Shaped Charge development, explosively-formed penetrator phenomena, hypervelocity impact cratering in metal targets, and long, dense rod penetration/perforation of thick metal targets. Although shock wave phenomena are precursors in all these processes, deformation twins are rarely observed in the residual, process microstructures. In the case of hypervelocity impact craters, no deformation twins are observed in the crater-related target microstructures. Microbands that appear to be related to twins are observed. Melt-related phenomena are observed only in the explosive weld-wave interfaces. Jetting phenomena related to Shaped Charges and crater rim formation are dominated by dynamic recrystallization, which provides a mechanism for extreme plastic flow in the solid state. Differences observed between rod penetration of rolled homogeneous armor and Ti-alloy thick targets manifest themselves in distinct microstructural differences that also do not include melt phenomena.
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comparison of beginning and ending microstructures in metal Shaped Charges as a means to explore mechanisms for plastic deformation at high rates
Journal of Materials Science, 1995Co-Authors: L.e. Murr, S. Pappu, C S Niou, Javier Sanchez, H K Shih, L Duplessis, L ZernowAbstract:Optical metallography and transmission electron microscopy (TEM) observations were made of a variety of forged or sputtered copper, molybdenum, and tantalum Shaped Charge components. The beginning Shaped Charge liner grain sizes and sub-structures were compared with those observed in residual (ending), recovered and corresponding jet fragments and slugs. The wide range of microstructures and evolutionary features of observed microstructures can be characterized by low-energy dislocation structure (LEDS) principles which are altered because the Shaped Charge deformation corresponds to hot working, and dynamic recovery and recrystallization play a prominent role. There is a prominent relationship between the starting liner grain size, Do, and the ratio Do/Ds, where Ds is the ending (slug or jet), steady-state grain size. As a consequence of this relationship, it appears that the volumetric stored energy, which depends upon the grain size and dislocation density (or degree of deformation), is the critical issue in controlling Shaped Charge jet stability.
Huanguo Guo - One of the best experts on this subject based on the ideXlab platform.
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penetration behavior of high density reactive material liner Shaped Charge
Materials, 2019Co-Authors: Huanguo Guo, Haifu Wang, Jianwen Xie, Yuanfeng ZhengAbstract:The traditional polytetrafluoroethylene (PTFE)/Al reactive material liner Shaped Charge generally produces insufficient penetration depth, although it enlarges the penetration hole diameter by chemical energy release inside the penetration crater. As such, a novel high-density reactive material liner based on the PTFE matrix was fabricated, and the corresponding penetration performance was investigated. Firstly, the PTFE/W/Cu/Pb high-density reactive material liner was fabricated via a cold pressing/sintering process. Then, jet formation and penetration behaviors at different standoffs were studied by pulse X-ray and static experiments, respectively. The X-ray results showed that the PTFE/W/Cu/Pb high-density reactive material liner forms an excellent reactive jet penetrator, and the static experimental results demonstrated that the penetration depth of this high-density reactive jet increased firstly and then decreased by increasing the standoff. When the standoff was 1.5 CD (Charge diameter), the penetration depth of this reactive jet reached 2.82 CD, which was significantly higher than that of the traditional PTFE/Al reactive jet. Moreover, compared with the conventional metal copper jet penetrating steel plates, the entrance hole diameter caused by this high-density reactive jet improved 29.2% at the same standoff. Lastly, the chemical reaction characteristics of PTFE/W/Cu/Pb reactive materials were analyzed, and a semi-empirical penetration model of the high-density reactive jet was established based on the quasi-steady ideal incompressible fluid dynamics theory.
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penetration behavior of reactive liner Shaped Charge jet impacting thick steel plates
International Journal of Impact Engineering, 2019Co-Authors: Huanguo Guo, Yuanfeng Zheng, Haifu WangAbstract:Abstract Reactive liner Shaped Charge jet (RLSCJ) penetrates thick steel plate by experiments and model analysis combined. The experimental reactive material liners with a density of about 2.3 g/cm3, composed of mass matched ratios of Al/PTFE powders, are consolidated by a cold pressing/sintering process. Four standoffs of 0.5, 1.0, 1.5, and 2.0 CD (Charge diameter) are selected to conduct the penetration experiments. The experimental results show that, compared with traditional metal liner Shaped Charge jet against thick steel plates, a relative larger hole diameter but lower depth accompanying with fragmentation effects of penetrating steel plates are produced by RLSCJ. To understand this penetration behavior of reactive jet, an analytical model is developed to discuss the influence of initiation delay time of reactive jet and standoff on penetration depth. Analysis shows that the penetration depth strongly depends on initiation delay time of reactive jet. With increasing the initiation delay time, the penetration depth increases significantly, showing a good agreement with the experiments. Moreover, to further understand the fragmentation mechanism effect of the thick steel plates, the effective mass of reactive jet inside the penetrating hole and its deflagration-induced structural damage effect are analyzed theoretically. Prediction results fit well with the experiments, including crack generation and propagation in the thick steel plates, and the number of fragments.
Zhifan Zhang - One of the best experts on this subject based on the ideXlab platform.
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sph fem simulation of Shaped Charge jet penetration into double hull a comparison study for steel and sps
Composite Structures, 2016Co-Authors: Zhifan Zhang, Longkan Wang, Vadim V Silberschmidt, Shiping WangAbstract:A high-speed metal jet capable to cause severe damage to a double-hull structure can be produced after detonation of a Shaped Charge. A Smoothed Particle Hydrodynamics (SPH) method with a mesh-free and Lagrange formulations has natural advantages in solving extremely dynamic problems. Hence, it was used to simulate the formation process of a Shaped-Charge jet. A Finite Element Method (FEM) is suitable for a structural analysis and is highly efficient for simulations of a complex impact process in a relatively short time; therefore, it was applied to develop a double-hull model. In this paper, a hybrid algorithm fully utilizing advantages of both SPH and FEM is proposed to simulate a metal-jet penetration into a double hull made of different materials – steel and SPS (Sandwich Plate System). First, a SPH-FEM model of a sphere impacting a plate was developed, and its results were compared with experimental data to validate the suggested algorithm. Second, numerical models of steel/SPS double-hull subjected to a Shaped-Charge jet were developed and their results for jet formation, a penetration process and a damage response were analysed and compared. The obtained results show that the velocity of the metal jet tended to decrease from its tip to the tail during its formation process. The jet broke into separate fragments after the first steel shell was penetrated, causing the damage zone of the second shell that grew as a result of continuous impact by fragments. As for the SPS structure, its damage zone was smaller, and the jet trended to bend becoming thinner due to the resistance of the composite layer. It was found that the polyurethane layer could have a protective effect for the second shell.
Yuanfeng Zheng - One of the best experts on this subject based on the ideXlab platform.
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penetration behavior of high density reactive material liner Shaped Charge
Materials, 2019Co-Authors: Huanguo Guo, Haifu Wang, Jianwen Xie, Yuanfeng ZhengAbstract:The traditional polytetrafluoroethylene (PTFE)/Al reactive material liner Shaped Charge generally produces insufficient penetration depth, although it enlarges the penetration hole diameter by chemical energy release inside the penetration crater. As such, a novel high-density reactive material liner based on the PTFE matrix was fabricated, and the corresponding penetration performance was investigated. Firstly, the PTFE/W/Cu/Pb high-density reactive material liner was fabricated via a cold pressing/sintering process. Then, jet formation and penetration behaviors at different standoffs were studied by pulse X-ray and static experiments, respectively. The X-ray results showed that the PTFE/W/Cu/Pb high-density reactive material liner forms an excellent reactive jet penetrator, and the static experimental results demonstrated that the penetration depth of this high-density reactive jet increased firstly and then decreased by increasing the standoff. When the standoff was 1.5 CD (Charge diameter), the penetration depth of this reactive jet reached 2.82 CD, which was significantly higher than that of the traditional PTFE/Al reactive jet. Moreover, compared with the conventional metal copper jet penetrating steel plates, the entrance hole diameter caused by this high-density reactive jet improved 29.2% at the same standoff. Lastly, the chemical reaction characteristics of PTFE/W/Cu/Pb reactive materials were analyzed, and a semi-empirical penetration model of the high-density reactive jet was established based on the quasi-steady ideal incompressible fluid dynamics theory.
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penetration behavior of reactive liner Shaped Charge jet impacting thick steel plates
International Journal of Impact Engineering, 2019Co-Authors: Huanguo Guo, Yuanfeng Zheng, Haifu WangAbstract:Abstract Reactive liner Shaped Charge jet (RLSCJ) penetrates thick steel plate by experiments and model analysis combined. The experimental reactive material liners with a density of about 2.3 g/cm3, composed of mass matched ratios of Al/PTFE powders, are consolidated by a cold pressing/sintering process. Four standoffs of 0.5, 1.0, 1.5, and 2.0 CD (Charge diameter) are selected to conduct the penetration experiments. The experimental results show that, compared with traditional metal liner Shaped Charge jet against thick steel plates, a relative larger hole diameter but lower depth accompanying with fragmentation effects of penetrating steel plates are produced by RLSCJ. To understand this penetration behavior of reactive jet, an analytical model is developed to discuss the influence of initiation delay time of reactive jet and standoff on penetration depth. Analysis shows that the penetration depth strongly depends on initiation delay time of reactive jet. With increasing the initiation delay time, the penetration depth increases significantly, showing a good agreement with the experiments. Moreover, to further understand the fragmentation mechanism effect of the thick steel plates, the effective mass of reactive jet inside the penetrating hole and its deflagration-induced structural damage effect are analyzed theoretically. Prediction results fit well with the experiments, including crack generation and propagation in the thick steel plates, and the number of fragments.