TOSELLO R , VIVES M , TRONCHE A . Twin EFPs for underwater applications [C ] // Proceedings of the 16th International Symposium on Ballistics . San Francisco, CA, US : International Ballistics Society , 1996 : 367 - 378 .

HONG S C , NIU Y M . Numerical simulation of the multiplayer explosively formed projectile [C ] // Proceedings of the 15th International Symposium on Ballistic . Jersusalem, Israel : International Ballistics Society , 1995 : 315 - 324 .

WEIMAN K , BLACHE A . Explosively formed projectile with tantalum penetration and steel stabilization base [C ] // Proceedings of the 18th International Symposium on Ballistics . San Antonio, TX, US : International Ballistics Society , 1999 : 603 - 608 .

FONG R , NG W , WERMAN K . Testing and analysis of multi-liner EFP warheads [C ] // Proceedings of the 20th International Symposium on Ballistics . Orlando, FL, US : International Ballistics Society , 2002 : 578 - 581 .

龙源 , 毛振兴 , 刘健峰 , 等 . 曲率半径对双层药型罩EFP战斗部成型及侵彻的影响 [J ] . 爆破器材 , 2016 , 45 ( 3 ): 5 - 10 .

LONG Y , MAO Z X , LIU J F , et al . Influence of curvature radius on the formation and penetration of explosively formed penetrator warhead of the double layer liner [J ] . Explosive Materials , 2016 , 45 ( 3 ): 5 - 10 . (in Chinese)

王维占 , 李小军 , 雷文星 , 等 . 包覆式双层EFP成型数值模拟 [J ] . 弹箭与制导学报 , 2018 , 38 ( 6 ): 103 - 108 .

WANG W Z , LI X J , LEI W J , et al . Numerical simulation of double-layer cladding EFP molding process [J ] . Journal of Projectiles, Rockets, Missiles and Guidance , 2018 , 38 ( 6 ): 103 - 108 . (in Chinese)

MA H B , ZHENG Y F , WANG H F , et al . Formation and impact-induced separation of tandem EFPs [J ] . Defence Technology , 2020 , 16 ( 3 ): 668 - 677 . DOI: 10.1016/j.dt.2019.09.003 http://doi.org/10.1016/j.dt.2019.09.003 The formation and separation behaviors of tandem EFPs are studied by the combination of experiments and simulations. The results show that different formation and separation processes can be obtained by adjusting the double-layer liners, and simulations agree with experiments well. Then, the interaction process between the two liners is discussed in details, and the formation and separation mechanism are revealed. It can be found that there are four phases in the formation and separation processes, including impact phase, propulsion phase, slide phase and free flight phase. During the impact phase, the velocities of two liners rise in turns with kinetic energy exchange. In the propulsion phase, the axial impact becomes insignificant, but the radial interaction between two liners influences the appearance of tandem EFPs. Meanwhile, it should be mentioned that the inner surface of foregoing EFP remains to be in contact with the outer surface of following EFP in the propulsion phase, and the following one would continue to push the foregoing one for about 10μ to 20 μs, causing the velocities of following and foregoing EFPs gradually decreasing and increasing respectively. In the slide phase, an obvious relative movement occurs between the two EFPs, and there would be barely kinetic energy exchange. Then, the two EFPs separate gradually and get into the phase of free flight. Generally, if the outer and inner liners have the same thickness, the outer copper-inner copper liners form two long EFPs, the outer copper-inner steel liners become a foregoing short steel EFP and a following long copper EFP, and the outer steel-inner copper liners produce a foregoing long copper EFP and a following conical steel EFP. In addition, thickness match also has an important impact on formation appearance and separation process for both outer copper-inner copper liners and outer steel-inner copper liners. With the thickness ratio of outer liner to inner liner decreasing, the length and length-diameter ratio of both foregoing and following EFPs increase gradually. © 2019 The Authors

王哲 , 蒋建伟 , 王树有 , 等 . 双层药型罩形成的串联爆炸成型弹丸速度计算模型 [J ] . 兵工学报 , 2017 , 38 ( 7 ): 1301 - 1306 . DOI: 10.3969/j.issn.1000-1093.2017.07.007 http://doi.org/10.3969/j.issn.1000-1093.2017.07.007 针对典型双层药型罩爆炸成型弹丸(EFP)装药结构，基于微元爆轰驱动及碰撞理论，考虑药型罩轴向驱动及径向压垮特性，建立了双层药型罩串联EFP速度分析模型。计算结果表明：罩微元径向压垮引起的内外罩EFP轴向速度差是串联EFP分离的核心因素；外罩EFP速度随外罩曲率及外罩所占厚度比增加而增加；内罩EFP速度随外罩曲率增加而减小，随外罩所占厚度比增加而增加。结合数值模拟与脉冲X光成型试验对所推导理论进行了验证，三者所得到的串联EFP速度吻合较好。

WANG Z , JIANG J W , WANG S Y , et al . A calculation model of velocity of tandem EFP with double layer liners [J ] . Acta Armamentarii , 2017 , 38 ( 7 ): 1301 - 1306 . (in Chinese) DOI: 10.3969/j.issn.1000-1093.2017.07.007 http://doi.org/10.3969/j.issn.1000-1093.2017.07.007 A velocity calculation model of tandem EFP is proposed by analyzing the motion of elements in double-layer liners. The analysis shows that the difference in EFP axial velocities caused by radial velocity plays an important role in the separation of the tandem EFP. The velocity of EFP formed by outside liner increases with the increase in the curvature of outside liner and the thickness ratio of outside liner to inside liner. On the other hand, the velocity of EFP formed by inside liner decreases with the increase in curvature of outside liner, but increases with the increase in thickness ratio of outside liner to inside liner. The calculated results agree well with experimental data and simulated results by LS-DYNA.Key

韩伟 , 何勇 , 沈晓军 , 等 . 锆钽复合药型罩EFP成型及侵彻研究 [J ] . 兵器装备工程学报 , 2019 , 40 ( 4 ): 163 - 173 .

HAN W , HE Y , SHEN X J , et al . Investigation of EFP forming and penetration of Ta/Zr double-layered shaped charge liner [J ] . Journal of Ordnance Equipment Engineering , 2019 , 40 ( 4 ): 163 - 173 . (in Chinese)

黄松 , 尹建平 , 张斐 , 等 . 多层串联EFP成型及侵彻对比分析研究 [J ] . 火工品 , 2018 ( 5 ): 25 - 28 .

HUANG S , YIN J P , ZHANG F , et al . Comparative analysis on shaping and penetration of the multi-layer EFP [J ] . Initiators & Pyrotechnics , 2018 ( 5 ): 25 - 28 . (in Chinese)

卢冠成 , 曹康 , 耿宝群 , 等 . 活性破片爆裂毁伤后效快速图像识别方法 [C ] // 第十二届全国爆炸力学学术会议缩编文集 . 桐乡 : 中国力学学会 , 2018 .

LU G C , CAO K , GENG B Q , et al . Rapid image recognition of rupturing damage to plates impacted by reactive fragment [C ] // Proceedings ot the 12th National Conference on Explosion Mechanics . Tongxiang : The Chinese Society of The Chinese Society of Theoretical and Applied Mechanics , 2018 . (in Chinese)

ZHENG Y F , SU C H , GUO H G , et al . Behind-target rupturing effects of sandwich-like plates by reactive liner shaped charge jet [J ] . Propellants Explosives, Pyrotechnics , 2019 , 44 : 1400 - 1409 . DOI: 10.1002/prep.v44.11 http://doi.org/10.1002/prep.v44.11 https://onlinelibrary.wiley.com/toc/15214087/44/11 https://onlinelibrary.wiley.com/toc/15214087/44/11

GUO J , ZHANG Q M , ZHANG L S , et al . Reaction behavior of Polytetrafluoroethylene-Al granular composites subjected to planar shock wave [J ] . Propellants, Explosives, Pyrotechnics , 2017 , 42 ( 3 ): 300 - 307 . DOI: 10.1002/prep.v42.3 http://doi.org/10.1002/prep.v42.3 http://doi.wiley.com/10.1002/prep.v42.3 http://doi.wiley.com/10.1002/prep.v42.3

武强 , 龚自正 , 张庆明 , 等 . 含能活性材料防护结构超高速撞击特性数值模拟研究 [J ] . 振动与冲击 , 2021 , 40 ( 11 ): 202 - 210 .

WU Q , GONG Z Z , ZHANG Q M , et al . Numerical simulation of hypervelocity impact characteristics of energetic active material protective structure [J ] . Journal of Vibration and Shock , 2021 , 40 ( 11 ): 202 - 210 . (in Chinese)

AMES R G . Energy release characteristics of impact-initiated energetic materials [J ] . MRS Online Proceedings Library , 2005 , 896 : 308 .

ZHENG Y F , SU C H , GUO H G , et al . Chain damage effects of multi-spaced plates by reactive jet impact [J ] . Defence Technology , 2021 , 17 ( 2 ): 393 - 404 . DOI: 10.1016/j.dt.2020.02.008 http://doi.org/10.1016/j.dt.2020.02.008 Chain damage is a new phenomenon that occurs when a reactive jet impacts and penetrates multi-spaced plates. The reactive jet produces mechanical perforations on the spaced plates by its kinetic energy (KE), and then results in unusual chain rupturing effects and excessive structural damage on the spaced plates by its deflagration reaction. In the present study, the chain damage behavior is initially demonstrated by experiments. The reactive liners, composed of 26 wt%Al and 74 wt% PTFE, are fabricated through a pressing and sintering process. Three reactive liner thicknesses of 0.08 CD, 0.10 CD and 0.12 CD (charge diameter) are chosen to carry out the chain damage experiments. The results show a chain rupturing phenomenon caused by reactive jet. The constant reaction delay time and the different penetration velocities of reactive jets from liners with different thicknesses result in the variation of the deflagration position, which consequently determines the number of ruptured plates behind the armor. Then, the finite-element code AUTODYN-3D has been used to simulate the kinetic energy only-induced rupturing effects on plates, based on the mechanism of behind armor debris (BAD). The significant discrepancies between simulations and experiments indicate that one enhanced damage mechanism, the behind armor blast (BAB), has acted on the ruptured plates. Finally, a theoretical model is used to consider the BAB-induced enhancement, and the analysis shows that the rupturing area on aluminum plates depends strongly upon the KE only-induced pre-perforations, the mass of reactive materials, and the thickness of plates. © 2020 The Authors

GUO H G , ZHENG Y F , YU Q B , et al . Penetration behavior of reactive liner shaped charge jet impacting steel plates [J ] . International Journal of Impact Engineering , 2019 , 126 : 76 - 84 . DOI: 10.1016/j.ijimpeng.2018.12.005 http://doi.org/10.1016/j.ijimpeng.2018.12.005 https://linkinghub.elsevier.com/retrieve/pii/S0734743X1830945X https://linkinghub.elsevier.com/retrieve/pii/S0734743X1830945X

郭焕果 , 卢冠成 , 何锁 , 等 . 活性复合罩聚能装药侵彻增强行为 [J ] . 北京理工大学学报 , 2020 , 40 ( 12 ): 1259 - 1266 .

GUO H G , LU G C , HE S , et al . Penetration enhancement behavior of reactive material double-layered liner shaped charge [J ] . Transactions of Beijing Institute of Technology , 2020 , 40 ( 12 ): 1259 - 1266 . (in Chinese)

REN S Y , ZHANG Q M , WU Q , et al . A reactive material double-bumper shield for centimeter sized projectile [J ] . International Journal of Impact Engineering , 2021 , 158 : 1 - 10 .

郑元枫 , 马红兵 , 肖艳文 , 等 . 三层串联EFP成型与分离行为 [J ] . 北京理工大学学报 , 2021 , 41 ( 2 ): 143 - 150 .

ZHENG Y F , MA H B , XIAO Y W , et al . Formation and separation behavior of the triple-layer EFP [J ] . Transactions of Beijing Institute of Technology , 2021 , 41 ( 2 ): 143 - 150 . (in Chinese)