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Haifu Wang - One of the best experts on this subject based on the ideXlab platform.
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Research on the Ignition Height and Reaction Flame Temperature of PTFE/Al/Si/CuO with Different Mass Ratios of PTFE/Si
'MDPI AG', 2021Co-Authors: Xuan Zou, Jingyuan Zhou, Wenhui Tang, Xianwen Ran, Ping Liu, Pengwan Chen, Haifu WangAbstract:Recent studies have shown that the energy release capacity of Polytetrafluoroethylene (PTFE)/Al with Si, and CuO, respectively, is higher than that of PTFE/Al. PTFE/Al/Si/CuO Reactive Materials with four proportions of PTFE/Si were designed by the molding–sintering process to study the influence of different PTFE/Si mass ratios on energy release. A drop hammer was selected for igniting the specimens, and the high-speed camera and spectrometer systems were used to record the energy release process and the flame spectrum, respectively. The ignition height of the Reactive Material was obtained by fitting the relationship between the flame duration and the drop height. It was found that the ignition height of PTFE/Al/Si/CuO containing 20% PTFE/Si is 48.27 cm, which is the lowest compared to the ignition height of other Si/PTFE ratios of PTFE/Al/Si/CuO; the flame temperature was calculated from the flame spectrum. It was found that flame temperature changes little for the same Reactive Material at different drop heights. Compared with the flame temperature of PTFE/Al/Si/CuO with four mass ratios, it was found that the flame temperature of PTFE/Al/Si/CuO with 20% PTFE/Si is the highest, which is 2589 K. The results show that PTFE/Al/Si/CuO containing 20% PTFE/Si is easier to be ignited and has a stronger temperature destruction effect
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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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damage effects of double spaced aluminum plates by Reactive Material projectile impact
International Journal of Impact Engineering, 2017Co-Authors: Yuanfeng Zheng, Moang Lei, Haifu WangAbstract:Abstract Damage effects of the double-spaced aluminum plates, impacted by the cold isostatically pressed and sintered PTFE/Al/W Reactive Material projectile with a density of 7.8 g/cm 3 , were investigated by the ballistic impact experiments and the theoretical analyses. Three kinds of the double-spaced plates with the thicknesses of 3 mm/3 mm, 6 mm/3 mm and 6 mm/6 mm were used. The distance between the front and the rear plate was 200 mm. The cylindrical Reactive projectile with the mass of 8 g was launched at the velocities of approximate 710 m/s∼950 m/s to impact the target. It has been shown that the plugging damage pattern is formed on the front plate impacted by the Reactive projectile. Moreover, damage to the rear plate is significantly influenced by the impact velocity and the front/ rear plate thickness. For mechanism consideration, the plugging damage to the front plate is caused by the kinetic energy impact of the Reactive projectile. However, damage to the rear plate is caused by the kinetic energy impact of residual projectile and fragment cloud. The chemical release may also enhance the damage to the rear plate.
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experimental study on behind plate overpressure effect by Reactive Material projectile
Propellants Explosives Pyrotechnics, 2017Co-Authors: Baoqun Geng, Xuepeng Zhang, Jianguang Xiao, Haifu WangAbstract:The behind-plate overpressure effect by a Reactive Material projectile with a density of 7.7 g cm−3 was investigated by ballistic impact and sealed chamber tests. The Reactive projectile was launched onto the initially sealed test chamber with a 2024-T3 aluminum cover plate with a thickness of 3 mm, 6 mm, and 10 mm, respectively. Moreover, the overpressure signals in the test chamber were recorded by a pressure sensor and a data acquisition system. The experimental results show that the behind-plate overpressure effect is significantly influenced by plate thickness and impact velocity. For a given plate thickness, the peak overpressure in the test chamber shows an increasing trend with increase of impact velocity. However, for a given impact velocity, when impacting the 6 mm thick aluminum plate, the peak overpressure measured and the impulse delivered to chamber are higher than the values recorded for the 3 mm and 10 mm thick aluminum plates. As such, it is inferred that there is an optimum plate thickness to maximize the behind-plate overpressure effect by Reactive projectile.
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Damage effects of aluminum plate by Reactive Material projectile impact
International Journal of Impact Engineering, 2017Co-Authors: Zheng Yuxuan, Xuepeng Zhang, Haifu WangAbstract:Abstract This investigation describes and analyzes the damage effects of 2024-T3 aluminum plates normally impacted by cold isostatically pressed and sintered PTFE/Al/W Reactive Material projectiles. In the experiments, the Reactive Material projectiles impacted 3 mm thick aluminum plates at velocities in the range from 289 to 569 m/s and impacted 12 mm thick aluminum plates at velocities in the range from 500 to 956 m/s. The damage patterns and the corresponding penetration-induced deflagration behavior are presented and analyzed. In addition, combining theoretical considerations with experimental results, the effect of impact velocity on the extent of petal bulge and the penetration hole sizes is analyzed. Moreover, by comparing the calculated results with the experimental data, the influences of chemical energy released from the Reactive Materials during penetration on the extent of petal bulge and the penetration hole sizes are investigated and discussed. As the results show, the damage of aluminum plates by Reactive Material projectile impact not only varies with the kinetic energy, but is also significantly influenced by the chemical energy released in the penetration process.
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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damage effects of double spaced aluminum plates by Reactive Material projectile impact
International Journal of Impact Engineering, 2017Co-Authors: Yuanfeng Zheng, Moang Lei, Haifu WangAbstract:Abstract Damage effects of the double-spaced aluminum plates, impacted by the cold isostatically pressed and sintered PTFE/Al/W Reactive Material projectile with a density of 7.8 g/cm 3 , were investigated by the ballistic impact experiments and the theoretical analyses. Three kinds of the double-spaced plates with the thicknesses of 3 mm/3 mm, 6 mm/3 mm and 6 mm/6 mm were used. The distance between the front and the rear plate was 200 mm. The cylindrical Reactive projectile with the mass of 8 g was launched at the velocities of approximate 710 m/s∼950 m/s to impact the target. It has been shown that the plugging damage pattern is formed on the front plate impacted by the Reactive projectile. Moreover, damage to the rear plate is significantly influenced by the impact velocity and the front/ rear plate thickness. For mechanism consideration, the plugging damage to the front plate is caused by the kinetic energy impact of the Reactive projectile. However, damage to the rear plate is caused by the kinetic energy impact of residual projectile and fragment cloud. The chemical release may also enhance the damage to the rear plate.
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formation and penetration of jets by shaped charges with Reactive Material liners
Propellants Explosives Pyrotechnics, 2016Co-Authors: Yongzhi Wang, Yuanfeng Zheng, Haifu WangAbstract:Reactive Material lining is an efficient damage enhancement technology that incorporates the defeat mechanisms of kinetic energy and chemical energy. The liners are fabricated by cold isostatically pressing at a pressure of 250 MPa. In this paper, the formation behaviors of jet with the polymer-based Reactive Material liner are investigated by numerical simulation and X-ray photographs. The corresponding simulations of jet formation are presented, and the results agree well with experimental ones. They show that the Reactive Material liner can shape almost continuous and straight jet. Compared with the conventional copper liner, the Reactive Material liner can shape jet in a shorter time, but the jet break easily and lose stability due to its poor ductility. Although the penetration depth is sacrificed slightly when penetrating steel target, the Reactive Material liner produce a significantly enlarged hole-diameter.
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impact induced initiation and energy release behavior of Reactive Materials
Journal of Applied Physics, 2011Co-Authors: Haifu Wang, Yuanfeng Zheng, Zongwei LiuAbstract:Reactive Material fragment is an extremely efficient damage enhancement technology that incorporates the defeat mechanisms of kinetic energy and chemical energy. In this paper, the polymer-based Reactive Material fragment/target interactions are investigated. Related dynamic testing techniques for energy release characteristics of Reactive Material fragments are presented, and a series of ballistic experiments is conducted. The results show the Reactive Material fragment, which perforates the closed test chamber, undergoes a violent chemical reaction under highly dynamic loads and releases great amounts of thermo-chemical energy on the interior. The impact-initiated process and energy release behavior are markedly influenced by the impact velocity, indicating the Material’s fracture is of importance to the reaction. A relationship between the maximum pressure inside the chamber and the reaction efficiency is derived to analyze the influence quantitatively, and the venting effects are also considered.
Baoru Yang - One of the best experts on this subject based on the ideXlab platform.
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red green currant and sea buckthorn berry press residues as potential sources of antioxidants for food use
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Anna Puganen, Heikki Kallio, Karen M Schaich, Jukkapekka Suomela, Baoru YangAbstract:The potential for using extracts of press residues from black, green, red, and white currants and from sea buckthorn berries as sources of antioxidants for foods use was investigated. Press residues were extracted with ethanol in four consecutive extractions, and total Folin–Ciocalteu (F–C) Reactive Material and authentic phenolic compounds were determined. Radical quenching capability and mechanisms were determined from total peroxyl radical-trapping antioxidant capacity (TRAP) and oxygen radical absorbance capacity (ORAC) assays and from diphenylpicrylhydrazyl (DPPH) kinetics, respectively; specific activities were normalized to F–C Reactive concentrations. Levels of total F–C Reactive Materials in press residue extracts were higher than in many fruits and showed significant radical quenching activity. Black currant had the highest authentic phenol content and ORAC, TRAP, and DPPH reactivity. Sea buckthorn grown in northern Finland showed extremely high total specific DPPH reactivity. These results sugg...
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Red/Green Currant and Sea Buckthorn Berry Press Residues as Potential Sources of Antioxidants for Food Use
2018Co-Authors: Anna Puganen, Karen M Schaich, Jukkapekka Suomela, Heikki P. Kallio, Baoru YangAbstract:The potential for using extracts of press residues from black, green, red, and white currants and from sea buckthorn berries as sources of antioxidants for foods use was investigated. Press residues were extracted with ethanol in four consecutive extractions, and total Folin–Ciocalteu (F–C) Reactive Material and authentic phenolic compounds were determined. Radical quenching capability and mechanisms were determined from total peroxyl radical-trapping antioxidant capacity (TRAP) and oxygen radical absorbance capacity (ORAC) assays and from diphenylpicrylhydrazyl (DPPH) kinetics, respectively; specific activities were normalized to F–C Reactive concentrations. Levels of total F–C Reactive Materials in press residue extracts were higher than in many fruits and showed significant radical quenching activity. Black currant had the highest authentic phenol content and ORAC, TRAP, and DPPH reactivity. Sea buckthorn grown in northern Finland showed extremely high total specific DPPH reactivity. These results suggest that berry press residues offer attractive value-added products that can provide antioxidants for use in stabilizing and fortifying foods
Thomas Gessner - One of the best experts on this subject based on the ideXlab platform.
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a novel technique for mems packaging Reactive bonding with integrated Material systems
Sensors and Actuators A-physical, 2012Co-Authors: Joerg Braeuer, Jan Besser, Maik Wiemer, Thomas GessnerAbstract:Abstract Considering the demand for low temperature bonding processes in 3D integration and packaging of microelectronic or micromechanical components, this paper introduces a method that uses a specific form of local heat generation, which is based on nano scale Reactive Material systems. Such systems consist of several layers of minimum two different Materials with nano scale thicknesses. These layers generate a self-propagating and exothermic reaction during their intermixing. The resulting heat can be used as the heat source for bonding processes such as solder bonding of micro components. In contrast to other researchers, who focus on relatively thick Ni/Al foils for joining macroscopic parts, we focus on the direct deposition of Reactive multilayer systems. The principle of this method is demonstrated by Reactive bonding, for which we use different energetic systems. The main part of this paper deals with the preparation and investigation of integrated Reactive Material systems.
Yuxuan Zheng - One of the best experts on this subject based on the ideXlab platform.
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experimental study on penetration behavior of Reactive Material projectile impacting aluminum plate
International Journal of Impact Engineering, 2016Co-Authors: Yuxuan Zheng, Ying Wang, Haifu WangAbstract:Abstract Ballistic impact experiments were performed on the cold isostatically pressed and sintered PTFE/Al/W Reactive Material projectile with a density of 7.8 g/cm3, in order to understand its penetration behavior of normally impacting 2024-T3 aluminum plates. The damage patterns of perforated and imperforated aluminum plates are observed and ballistic limit velocities are obtained by using experimental results. The penetration-induced deflagration behavior of Reactive Material projectile normally impacting aluminum plates with different thickness at approximate ballistic limit velocity is also analyzed. Combining the THOR penetration equation with experimental results, a semi-empirical relationship is developed to predict the ballistic limit velocity of Reactive Material projectile impacting aluminum plates. Moreover, the target thickness and the projectile mass effects on penetration performance of Reactive Material projectile relative to steel projectile impacting aluminum plates are analyzed and discussed. As the analyses show, when the Reactive Material projectile impacts aluminum plates at approximate ballistic limit velocity, an increasing target thickness always means that the delaying rarefaction wave effect, the dropping initial shock wave attenuation effect, and the decreasing time after impact for initiation. Hence more Reactive Materials are initiated to deflagrate in the penetration channel, enhancing the influence of chemical energy released on penetration-induced deflagration behavior and penetration performance.
