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Ballistic limit velocity of small caliber projectiles against SS400 steel plates:Live fire experiments and empirical models
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作者 Jong-Hwan Kim Seungwon Baik +1 位作者 Jirui Fu Joon-Hyuk Park 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期22-34,共13页
This study presents the ballistic limit velocity of small caliber projectiles against SS400 steel plate derived from live-fire ballistic experiments. Four different small caliber projectiles were tested against SS400 ... This study presents the ballistic limit velocity of small caliber projectiles against SS400 steel plate derived from live-fire ballistic experiments. Four different small caliber projectiles were tested against SS400 steel plates of 9 mm, 10 mm, and 12 mm thicknesses. The ballistic limit velocity was calculated using two standard methods, MIL-STD-662F and NIJ-STD-0101.06, and additionally using a support vector machine algorithm. The results show a linear relationship between the plate thickness and ballistic limit velocity. Further, the relative penetration performance among five different small caliber projectiles was analyzed using the Penetration Performance Ratio(PPR) introduced in this study, which suggests the potential of PPR to predict the ballistic limit velocity of other untested materials and/or different projectiles. 展开更多
关键词 Live fire ballistic experiment SS400 Ballistic limit velocity Small caliber projectile
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Ballistic response of skin simulant against fragment simulating projectiles
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作者 Punit Kumar Pandey Atul Harmukh +2 位作者 M.K.Khan M.A.Iqbal S.G.Ganpule 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期70-82,共13页
The response of biological phantoms against high velocity impact is actively sought for applications in defense,space,soft robotics and sensing.Towards this end,we study the ballistic response of silicone based skin s... The response of biological phantoms against high velocity impact is actively sought for applications in defense,space,soft robotics and sensing.Towards this end,we study the ballistic response of silicone based skin simulant against fragment impact.Using a pneumatic gas gun setup,six chisel-nosed and three regular shaped(sphere,cylinder,and cube)fragments were impacted on the skin simulant.The resulting skin simulant response was studied in terms of ballistic limit velocities,energy densities,failure pattern,and the mechanics of interaction.The results indicate that the shape of the fragment affects the ballistic limit velocities.The ballistic limit velocities,energy densities of the chisel-nosed fragment simulating projectiles were relatively insensitive to the size(mass),except for the smallest(0.16 g)and largest(2.79 g)chisel-nosed fragment.For the same size(1 g),ballistic limit velocities and failure are dependent on the shape of the fragment.The skin simulant failed by combined plugging and elastic hole enlargement.Failure in the spherical fragment was dominated by the elastic hole enlargement,whereas plugging failure was dominant in all other fragments.The spherical,cylindrical,and chisel-nosed fragments created circular cavities,and the cubical fragment created a square cavity.In the case of the spherical fragment,slipping of the fragment within the skin simulant was seen.Cubical fragments created lateral cracks emanating from the corners of the square cavity.Interestingly,for all the fragments,the maximum deformation corresponding to the perforation was lower than the non-perforation indicating rate dependent,stress driven failure.The maximum deformation was also dependent on the shape of the fragment.Overall,these results provide unique insights into the mechanical response of a soft simulant against ballistic impact.Results have utility in the calibration and validation of computational models,design of personal protective equipment,and antipersonnel systems. 展开更多
关键词 Skin simulant FRAGMENT Impact Ballistic limit velocity Energy density FAILURE
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Behind-plate overpressure effect of steel-encased reactive material projectile impacting thin aluminum plate 被引量:4
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作者 Qing-bo Yu Jia-hao Zhang +2 位作者 Hong-wei Zhao Yan-wen Xiao Hai-fu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第5期723-734,共12页
Ballistic impact and sealed chamber tests were performed on the steel-encased reactive material projectile(SERMP)to understand its behind-plate overpressure effect when impacting the thin aluminum plates.The reactive ... Ballistic impact and sealed chamber tests were performed on the steel-encased reactive material projectile(SERMP)to understand its behind-plate overpressure effect when impacting the thin aluminum plates.The reactive material encased with a 1.5 mm thick 30CrMnSiNi2A steel shell was launched onto the initially sealed test chamber with a 3 mm thick 2024-T3 thin aluminum cover plate.Moreover,the overpressure signals in the test chamber were recorded by pressure sensors.The experimental results indicate an unusual behind-plate overpressure effect:as the density of the projectile increases from 6.43 g/cm^(3) to 7.58 g/cm^(3) by increasing the content of tungsten powder,although its total chemical energy decreases,it produces a higher behind-target overpressure at a lower impact velocity.A theoretical model is proposed to predict the reaction length of reactive material inside the projectile based on one-dimensional shock wave theory to understand this unexpected result.In addition,the deviation between the actual energy release and the theoretical calculation results,also the variation of overpressure rise time are analyzed and discussed.As the analyses show,when the SERMP successfully penetrates the cover plate,an increasing density of the reactive material inside the projectile always means that the delaying rarefaction wave effect,an increase of its internal pressure and strain rate levels.These factors lead to the increase of the overpressure limit velocity and reaction extent of the reactive material,while the overpressure rise time decreases. 展开更多
关键词 Reactive materials Steel-encased reactive material projectile Over-pressure effect Overpressure limit velocity Energy release
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Semi-theoretical analyses of the concrete plate perforated by a rigid projectile 被引量:3
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作者 Hao Wu Qin Fang +1 位作者 Ya-Dong Zhang Zi-Ming Gong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第6期1630-1643,共14页
Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic per- formances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistanc... Based on the three-stage perforation model, a semi-theoretical analysis is conducted for the ballistic per- formances of a rigid kinetic projectile impacting on concrete plates. By introducing the projectile resistance coefficients, dimensionless formulae are proposed for depth of penetra- tion (DOP), perforation limit thickness, ballistic limit veloc- ity, residual velocity and perforation ratio, with the projec- tile nosed geometries and projectile-target interfacial fric- tion taken into account. Based on the proposed formula for DOP and lots of penetration tests data of normal and high strength concrete targets, a new expression is obtained for target strength parameter. By comparisons between the re- sults of the proposed formulae and existing empirical formu- lae and large amount of projectile penetration or perforation tests data for monolithic and segmented concrete targets, the validations of the proposed formulae are verified. It is found that the projectile-target interfacial friction can be neglected in the predictions of characteristic ballistic parameters. The dimensionless DOP for low-to-mid speed impacts of non-flat nosed projectiles increases almost linearly with the impact factor by a coefficient of 2/(nS). The anti-perforation ability of the multilayered concrete plates is dependent on both the target plate thickness and the projectile impact velocity. The variation range of the perforation ratio is 1-3.5 for concrete targets. 展开更多
关键词 PROJECTILE Concrete Depth of penetration Perforation limit thickness Ballistic limit velocity Resid-ual velocity
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Equivalent protection factor of bi-layer ceramic metal structures 被引量:4
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作者 Govind Gour Sridhar Idapalapati +1 位作者 Wei Liang Goh Xiao-peng Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期384-400,共17页
With increasing ballistic threat levels,there is ever more demand on developing ceramic armor designs with improved performance.This paper presents finite element simulations that investigate the performance of silico... With increasing ballistic threat levels,there is ever more demand on developing ceramic armor designs with improved performance.This paper presents finite element simulations that investigate the performance of silicon carbide ceramic with steel 4340 backing material and titanium alloy,graphite as buffer layers when subjected to normal and oblique impacts by a tungsten alloy long rod projectile(LRP).Depth of penetration from experimental measurements is compared with simulations to confirm the validity of constitutive,failure model parameters.Titanium alloy cover plate and graphite interface weak layer laterally spread the impact shock away from the SiC tile and reduces the amplification of the stress accumulation at the front surface of the SiC tile.The dwelling time increases before it penetrates into ceramic armor.Further,using AUTODYN®numerical simulations detailed parametric study is carried out to identify the minimum areal density armor for a given ballistic limit velocity.The equivalent protection factor for the bi-layer armor is a simple function of the cosine of the angle of impact. 展开更多
关键词 Ceramic armor Normal and NATO 60⁰impact Ballistic limit velocity Equivalent protection factor(EPF)
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Influences of nanotwin volume fraction on the ballistic performance of coarse-grained metals
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作者 Q.D.Ouyang G.J.Weng +1 位作者 A.K.Soh X.Guo 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2017年第5期265-268,共4页
Coarse-grained(CG) metals strengthened by nanotwinned(NT) regions possess high strength and good ductility. As such, they are very suitable for applications in bullet-proof targets. Here, a numerical model based o... Coarse-grained(CG) metals strengthened by nanotwinned(NT) regions possess high strength and good ductility. As such, they are very suitable for applications in bullet-proof targets. Here, a numerical model based on the conventional theory of strain gradient plasticity and the Johnson–Cook failure criterion is employed to study the influences of volume fraction of NT regions on their ballistic performance.The results show that in general a relatively small twin spacing(4–10 nm) and a moderate volume fraction(7%–20%) will lead to excellent limit velocity and that the influences of volume fraction on limit displacement change with the category of impact processes. 展开更多
关键词 Nanotwin Ballistic performance Volume fraction Limit velocity Limit displacement
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TIME-OPTIMAL INTERPOLATION FOR CNC MACHINING ALONG CURVED TOOL PATHES WITH CONFINED CHORD ERROR 被引量:4
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作者 YUAN Chunming ZHANG Ke FAN Wei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第5期836-870,共35页
In this paper, two new interpolation algorithms lot CNC machining along curve^l tom pathes are proposed: a time-optimal interpolation algorithm under chord error, feedrate, and tangential acceleration bounds, and a g... In this paper, two new interpolation algorithms lot CNC machining along curve^l tom pathes are proposed: a time-optimal interpolation algorithm under chord error, feedrate, and tangential acceleration bounds, and a greedy interpolation algorithm under the chord error and tangential jerk bounds. The key idea is to reduce the chord error bound to a centripetal acceleration bound which leads to a velocity limit curve, called the chord error velocity limit curve. Then, the velocity planning is to find the proper velocity curve governed by the acceleration or jerk bounds '~under" the chord error velocity limit curve. For two types of simple tool pathes, explicit formulas for the velocity curve are given and the methods are implemented in commercial CNC controllers. 展开更多
关键词 Chord error CNC interpolation cubic PH curve JERK quadratic B-spline time-optimalvelocity planning velocity limit curve.
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Penetration of disk fragments following impact on thin plate 被引量:6
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作者 Juan-juan LI Hai-jun XUAN +2 位作者 Lian-fang LIAO Wei-rong HONG Rong-ren WU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第5期677-684,共8页
To investigate the ballistic resistance and failure pattern of aeroengine casing following the impact of disk fragments, and to determine the optimum case structure, the phenomena of a 1/3rd disk fragment impact on si... To investigate the ballistic resistance and failure pattern of aeroengine casing following the impact of disk fragments, and to determine the optimum case structure, the phenomena of a 1/3rd disk fragment impact on single and double-layered thin plate targets were simulated using nonlinear dynamical analysis software MSC.Dytran. Strain rate effect was introduced in a Johnson-Cook (JC) material model for the disk fragment and the plate. Impact modeling was based on the Arbitrary Lagrange-Eulerian method, and simulated using explicit finite element method (FEM). Simulation results showed that the major failure pattern of the plate is shearing and tensile fracture with large plastic deformation. It was also concluded that the ballistic limit velocity increases with the standoff distance when it is beyond a certain value, and that greater resistance is obtained when the front plate has either a proportionately low or high thickness. The impact resistance of a double-layered plate may exceed that of a single plate if the thicknesses and standoff distance of the two plates are set appropriately. 展开更多
关键词 AEROENGINE Disk burst failure Case containment capability Ballistic limit velocity
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Hot electron transport in wurtzite-GaN:effects of temperature and doping concentration
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作者 Aritra Acharyya 《Journal of Semiconductors》 EI CAS CSCD 2018年第7期48-53,共6页
The hot electron transport in wurtzite phase gallium nitride(Wz-GaN) has been studied in this paper. An analytical expression of electron drift velocity under the condition of impact ionization has been developed by... The hot electron transport in wurtzite phase gallium nitride(Wz-GaN) has been studied in this paper. An analytical expression of electron drift velocity under the condition of impact ionization has been developed by considering all major scattering mechanisms such as deformation potential acoustic phonon scattering, piezoelectric acoustic phonon scattering, optical phonon scattering, electron-electron scattering and ionizing scattering. Numerical calculations show that electron drift velocity in Wz-GaN saturates at 1.44 ×10^5 m/s at room temperature for the electron concentration of 10^22 m^-3. The effects of temperature and doping concentration on the hot electron drift velocity in Wz-GaN have also been studied. Results show that the saturation electron drift velocity varies from 1.91 ×10^5-0.77 ×10^5 m/s for the change in temperature within the range of 10-1000 K, for the electron concentration of 10^22 m^-3; whereas the same varies from 1.44 ×10^5-0.91 ×10^5 m/s at 300 K for the variation in the electron concentration within the range of 10^22-10^25 m^-3. The numerically calculated results have been compared with the Monte Carlo simulated results and experimental data reported earlier, and those are found to be in good agreement. 展开更多
关键词 electron drift velocity hot electron transport GAN scattering limited velocity
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