Pub Date : 2019-07-30DOI: 10.21741/9781644900338-17
T. Saburi, S. Kubota, Y. Ogata, Yasumori Takahashi
Tensile strength test of rock at high strain rate was experimentally performed by utilizing the nature of the strength difference. A magnitude of the tensile strength of brittle materials such as rock is much smaller than that of compressive strength. A compressive wave was produced by dynamic loading of explosive charge and made incident on a one end of a rock specimen bar. The compressive wave traveled through the specimen bar and it reflected at the free surface of the opposite end as a tensile wave with reversal amplitude. The tensile wave will cause the spall failure of the specimen at a specific distance from the free surface where the superposition of tensile and compressive waves exceeds the tensile failure strength of the specimen, usually referred to as Hopkinson effect. The dynamic behavior was observed at the side face of the bar specimen using a high-speed video camera, and the captured images were used to analyze the surface displacement behavior using a digital image correlation (DIC) technique. Strain and strain rate distributions on the specimen bar during impact loading were evaluated. The relationship between strain rate and dynamic tensile strength was discussed. Introduction Dynamic tensile strength is an important factor affecting rock fracturing and fragmentation during blasting operation in quarries and mines. For the dynamic strength test, the Split Hopkinson Pressure Bar (SHPB) is widely applied because of the wide range of strain rate applicability. Regarding the application of the SHPB method to brittle materials, there are many studies [1,2] such as concrete and rock materials for compressive strength. The SHPB method can be applied not only by the indirect tension [3] but also by the direct tension [4] for tensile strength. However, when the sample is rock, the pressure bars sandwiching the sample should be jointed even in the tension state. In the case of rock mass test materials, it is specified or recommended that the sample core diameter is 50 mm or more in ASTM [5] and 54 mm or more in ISRM [6] in indirect tension (Brazilian) test to secure the diameter of the material to some content from the presence of crystals and wrinkles. It is necessary to secure the diameter on the side of the incident bar and the transmission bar, and there is a concern that the system as the SHPB test device will become extensive. Therefore, we apply the dynamic tensile strength test using the Hopkinson effect in this study. Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 97-102 https://doi.org/10.21741/9781644900338-17 98 Experiments The outline of the test equipment is shown in Fig.1. An explosive is placed on one end face of a cylindrical rock sample with a diameter of 30 mm. An explosive is detonated by the EBW detonator and impact pressure is applied to the sample. Thereby, a compressive stress wave propagates in the sample, and when it reaches the free end
利用强度差的性质，对岩石进行了高应变率下的抗拉强度试验。岩石等脆性材料的抗拉强度比抗压强度小得多。通过装药动载产生压缩波，并将压缩波入射到岩样杆的一端。压缩波穿过试件杆，在试件另一端的自由表面反射为振幅反转的拉伸波。当拉伸波和压缩波的叠加超过试样的拉伸破坏强度时，拉伸波会在距离自由表面一定距离处引起试样的剥落破坏，通常称为霍普金森效应。利用高速摄像机对试件侧面的动态行为进行观察，并利用数字图像相关(DIC)技术对其表面位移行为进行分析。评估了冲击加载过程中试件杆上的应变和应变率分布。讨论了应变速率与动态抗拉强度的关系。在采石场和矿山爆破作业中，动抗拉强度是影响岩石破碎的重要因素。在动强度试验中，分离式霍普金森压杆(SHPB)因其应变率适用范围广而得到了广泛的应用。关于SHPB方法在脆性材料中的应用，有很多研究[1,2]，如混凝土、岩石材料的抗压强度。SHPB法既可用于间接拉伸[3]，也可用于直接拉伸[4]。但当试样为岩石时，夹在试样中间的压杆即使处于受拉状态也应节理。对于岩石测试材料，在ASTM[5]中指定或建议样品岩心直径为50mm或更大，在间接拉伸(巴西)测试中ISRM[6]为54mm或更大，以确保材料直径不受晶体和褶皱的影响。有必要确保入射杆和传动杆侧的直径，担心该系统作为SHPB测试装置会变得广泛。因此，本研究采用Hopkinson效应进行动态拉伸强度试验。爆炸激波与高应变率现象材料研究论坛LLC材料研究学报第13期(2019)97-102 https://doi.org/10.21741/9781644900338-17 98实验试验设备外形如图1所示。将炸药放置在直径为30毫米的圆柱形岩石样品的一端面上。用EBW雷管引爆炸药，并对样品施加冲击压力。这样，压应力波在试样中传播，当它到达试样另一侧的自由端时，被反射为拉应力波。反射的拉伸应力波传播的区域是与随后到达的压缩波混合的区域。压应力减去拉应力的净拉伸状态导致试样在足以劈裂的点处断裂，试样导致剥落。通过评估此时发生解理的位置和时间计算出的拉应力的时间变化，以及试样自由端可以测量到的位移速度，可以根据自由面到断口的距离和时间估算出动态抗拉强度。利用激光多普勒位移仪测量了自由表面上的位移速度，并利用高速摄像机图像分析了裂缝的位置和时间。测量仪器为Ono Sokki公司LV-1610激光测振仪(He-Ne 663 nm)，用于样品端振动测量。采用高速相机SHIMADZU HPV-X(单声道，400 × 240像素)对冲击波在试样中传播的应力波产生的侧面位移进行测量。利用两台高速摄像机，可以进行三维位移分析，但目前只能用一台摄像机进行一个轴向的畸变分析。拍摄速度为50万帧/秒。利用应变片黏贴法(包括SHPB法)对试样中的应力传播进行了评估。虽然应变片只能跟踪附着点局部应变的时程，但随着数字成像技术和数值计算技术[7]的最新发展，通过光学观测在大视场范围内进行应变测量的数字图像相关。 扩展了数字图像相关(DIC)方法的应用范围，利用高速摄像机可以在全视场范围内获得高应变范围内的动态应变分布。虽然利用Hopkinson效应在拉伸断裂研究中进行了高速摄像机的观察[8,9]，但一直用于整个视场的动态畸变分析，仅用于断裂面图像的判断，实例很少。通过激光测振仪测量试样自由表面的振动速度和高速摄像机的DIC应变分析，分析了岩石材料在动态拉伸条件下的行为，阐明了其与拉伸破坏的关系。作为评价试验的样本，我们使用了长崎县生产的Isahaya砂岩。表1显示了典型的力学性能。一般情况下，如岩石材料，其抗拉强度远低于抗压强度，可见材料在抗拉作用下较弱。本试验方法是利用岩石材料抗压强度和抗拉强度特性差异的试验方法。表1 Isahaya砂岩材料特性Isahaya砂岩杨氏模量，E [GPa] 32泊松比，ν[-] 0.39密度，ρ [g/cm] 2.44单轴抗压强度，fc [MPa] 182劈裂抗拉强度，fspu [MPa] 9.9爆炸冲击波与高应变率现象Materials Research Forum LLC Materials Research Proceedings 13 (2019) 97-102 https://doi.org/10.21741/9781644900338-17 99图1实验装置原理图(当前系统:一个摄像头用于2D-DIC，无缓冲剂)。图2用于DIC分析的样品样品喷射散斑图。图3拍摄后的样品图片。图4自由面位移速度。爆炸冲击波与高应变率现象Materials Research Forum LLC Materials Research Proceedings第13(2019)期97-102 https://doi.org/10.21741/9781644900338-17 100结果与讨论试样射击后的图片如图3所示。在距自由面33 mm和55 mm处发现了两个小片裂缝。自由面上的位移速度如图4所示。波前在约85 us后到达自由表面，此后在约135 us时最大位移速度约为6.35 m/s。对高速摄像机拍摄的图像进行DIC分析得到试样区域内的应变分布和每10us应变率分布的时间历程分别如图5和图6所示。通过DIC分析，我们成功地可视化了高应变区在冲击载荷作用下随压缩波传播的扩展和传播过程。此外，观察到压缩波在自由端以拉伸波的形式反射，这导致应变分布发生逆转，在拉伸状态达到最大值的点处局部产生断裂。断裂点应变和应变速率分别高达0.046和50 s。提取应变线形随试样变化的时间历程如图7所示。可以证实，在反射波到达自由表面95 us后，在两个断点之间的区域开始出现张力状态。透射压缩波前时程如图8所示。锋面的传播速度由地块斜率估计，估计为3315 m/s，比表1参考数值计算得到的弹性波速低40%。通过DIC分析，断口处峰值位移速度dU/dt为1.83 m/s，与假设自由面反射的自由面峰值位移速度的一半相比，dU/dt相对较低，如图4所示。图5 DIC (exx)分析的应变分布序列图6 DIC (dexx/dt)分析的应变率分布序列爆炸激波和高应变率现象Materials Research Forum LLC Materials Research Proceedings 13 (2019) 97-102 https://doi.org/10.21741/9781644900338-17 101图7 DIC分析结果提取的应变曲线(exx)。图8透射压缩波前时程。为了阐明岩石材料的动态拉伸破坏行为，基于霍普金森效应，提出了基于剥落试验的炸药冲击载荷下单轴动态拉伸试验，并在砂岩上进行了试验。采用数字图像相关(DIC)方法对试样的动态应变分布和应变率分布进行了分析和可视化。结果表明，高应变区随压缩波的传播而扩展和扩展。
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Pub Date : 2019-07-30DOI: 10.21741/9781644900338-20
H. Khawaja, M. Moatamedi, Z. Andleeb, C. Strand, P. Chen, B. Guo
With increasing popularity of Carbon Fiber Reinforced Polymer (CFRP) over time, the need for research in the field has increased dramatically. Many industries, i.e. aeronautical, automotive, and marine are opting to install carbon fiber in their structures to account for harsh environments like cold temperatures applications, but the research on the temperature exposure behavior of the materials are limited. This study aims to investigate the impact resistance of CFRP samples using the air gun tests. Two different shaped pellets (Diabolo and Storm pellets) were used in this work. The pellets speeds were calculated using a high-speed camera. The tests were performed in the room temperature (22°C) as well as in the cold room where the test pieces were exposed to about -28°C for seven days. The experimental studies were performed and compared against finite element simulations using ANSYS®. The studies also included layering of the CFRP samples to find the limiting thickness of pellets penetration. It was concluded that the thickness of 0.79mm and below of CFRP, cannot resist the impact of pellets. The visual inspection of failure revealed that the CFRP has gone through a brittle failure. However, temperature was found to have no significant impact on the results as similar behavior of CFRP was observed in both room conditions (22°C) and cold temperatures (-28°C). Introduction In the last decades, a growing interest has been dedicated in the use of composite materials for structural applications. CFRP composites are gaining a special attention to replace traditional materials in several fields although it is well known that these systems are highly susceptible to internal damage caused by transverse loads even under low-velocity ones [1,2]. In general, CFRP composites can be damaged on the surface and also beneath the surface by relatively light impacts causing invisible impact damage [3]. Therefore, this study has been carried out both to highlight effects of variables linked to geometrical parameters of composite sheets, impactor, and operative conditions. Therefore, this study has been carried out both to highlight effects of variables linked to geometrical parameters of composite sheets, impactor, and operative conditions. Operative conditions affect the material properties as reported in [4-6]. Experimental Setup a. Test Samples Test samples used in this study were from the DragonPlate®, manufactured by Allred and Associates Inc., Elbridge, New York [7]. The CFRP samples used were EconomyPlateTM Solid Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 115-120 https://doi.org/10.21741/9781644900338-20 116 Carbon Fiber Sheet ~ 1/32" x 12" x 12" (0.79375mm x 304.8mm x 304.8mm) [8]. EconomyPlateTM sheets comprised of orthotropic (non-quasi-isotropic) at 0°/90° orientation laminates [9] (Figure 1.) utilizing a twill weave [10] (Figure 2.), while maintaining a symmetrical and bal
{"title":"Multiphysics Impact Analysis of Carbon Fiber Reinforced Polymer (CFRP) Shell","authors":"H. Khawaja, M. Moatamedi, Z. Andleeb, C. Strand, P. Chen, B. Guo","doi":"10.21741/9781644900338-20","DOIUrl":"https://doi.org/10.21741/9781644900338-20","url":null,"abstract":"With increasing popularity of Carbon Fiber Reinforced Polymer (CFRP) over time, the need for research in the field has increased dramatically. Many industries, i.e. aeronautical, automotive, and marine are opting to install carbon fiber in their structures to account for harsh environments like cold temperatures applications, but the research on the temperature exposure behavior of the materials are limited. This study aims to investigate the impact resistance of CFRP samples using the air gun tests. Two different shaped pellets (Diabolo and Storm pellets) were used in this work. The pellets speeds were calculated using a high-speed camera. The tests were performed in the room temperature (22°C) as well as in the cold room where the test pieces were exposed to about -28°C for seven days. The experimental studies were performed and compared against finite element simulations using ANSYS®. The studies also included layering of the CFRP samples to find the limiting thickness of pellets penetration. It was concluded that the thickness of 0.79mm and below of CFRP, cannot resist the impact of pellets. The visual inspection of failure revealed that the CFRP has gone through a brittle failure. However, temperature was found to have no significant impact on the results as similar behavior of CFRP was observed in both room conditions (22°C) and cold temperatures (-28°C). Introduction In the last decades, a growing interest has been dedicated in the use of composite materials for structural applications. CFRP composites are gaining a special attention to replace traditional materials in several fields although it is well known that these systems are highly susceptible to internal damage caused by transverse loads even under low-velocity ones [1,2]. In general, CFRP composites can be damaged on the surface and also beneath the surface by relatively light impacts causing invisible impact damage [3]. Therefore, this study has been carried out both to highlight effects of variables linked to geometrical parameters of composite sheets, impactor, and operative conditions. Therefore, this study has been carried out both to highlight effects of variables linked to geometrical parameters of composite sheets, impactor, and operative conditions. Operative conditions affect the material properties as reported in [4-6]. Experimental Setup a. Test Samples Test samples used in this study were from the DragonPlate®, manufactured by Allred and Associates Inc., Elbridge, New York [7]. The CFRP samples used were EconomyPlateTM Solid Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 115-120 https://doi.org/10.21741/9781644900338-20 116 Carbon Fiber Sheet ~ 1/32\" x 12\" x 12\" (0.79375mm x 304.8mm x 304.8mm) [8]. EconomyPlateTM sheets comprised of orthotropic (non-quasi-isotropic) at 0°/90° orientation laminates [9] (Figure 1.) utilizing a twill weave [10] (Figure 2.), while maintaining a symmetrical and bal","PeriodicalId":415881,"journal":{"name":"Explosion Shock Waves and High Strain Rate Phenomena","volume":"48 1-4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132781669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-30DOI: 10.21741/9781644900338-21
D. Pal, Shallu Gupta, D. Jindal, A. Kumar, A. Aggarwal, P. Lata
Physical properties such as particle size, surface area and shape of explosive control the rapidity and reliability of initiation, and detonation and thus determine the performance of an explosive device such as slapper detonators. In this paper, Nozzle assisted solvent/antisolvent (NASAS) process for recrystallisation of CL-20 explosive is established. Many process parameters are involved which affect the particle size of the explosive. Therefore an accurate prediction of particle size is required to tailor the particle size. In the present work, an intelligent algorithm is applied to build a simplified relationship between recrystallization process parameters and particle size. This can be used to predict explosive particle size with a wide range of process parameters through an adaptive neuro-fuzzy inference system (ANFIS). The model is trained using experimental data obtained from design of experiment techniques utilizing a MATLAB software. Six process parameters such as Solution pressure, Antisolvent pressure, Antisolvent temperature, Stirrer speed, Solution concentration and Nozzle diameter are used as input variables of the model and the particle size is used as the output variable. The predicted results are in close agreement with experimental values and the accuracy of the model has been tested by comparing the simulated data with actual data from the explosive recrystallization experiments and found to be inacceptable range with maximum absolute percentage error of 11.52 %. The ultrafine CL-20 prepared by NASAS process is used in Slapper detonator application. The threshold initiation voltages for CL-20 based slapper detonator is found to be in the range of 0.9 kV with standard deviation of ±0.1 kV. Introduction The physical properties such as crystal particle size, shape, morphology, crystalline imperfections, purity and microstructure of the inter-crystalline voids of an existing explosive can be altered. There are wide variety of processes available for tailoring particle size and morphology of energetic materials such as solvent/non-solvent recrystallization[1],continuous crystallization of submicrometer energetic materials [2], spray flash evaporation [3]Yang et al. [4] obtained nanoTATB by using solvent/anti-solvent method with a particle size of 60 nm approximately through atomization of solution by a nozzle to small droplets and colliding rapidly with non-solvent flow. There is a need of mathematical model to predict particle characteristics as a function of process parameters to provide a basis for a computer based process control system. Shallu Gupta et al.[5,6], used micro nozzle assisted spraying process (MNASP) for recrystallization of Submicrometer Hexanitrostilbene (sm-HNS) Explosive. The process attributes were optimized using weighted average techniques of Analytical Network Process (ANP). The advantages of neural network based Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials R
炸药的粒度、表面积和形状等物理性质控制着起爆和爆轰的速度和可靠性，从而决定了击波雷管等爆炸装置的性能。本文建立了用喷嘴辅助溶剂/反溶剂(NASAS)法对CL-20炸药进行再结晶的工艺。涉及到许多影响炸药粒度的工艺参数。因此，需要对粒径进行准确的预测，以调整粒径。在本工作中，应用智能算法建立再结晶工艺参数与粒度之间的简化关系。这可以通过自适应神经模糊推理系统(ANFIS)来预测具有广泛工艺参数的炸药粒度。利用MATLAB软件对实验技术设计中得到的实验数据进行模型训练。采用溶液压力、反溶剂压力、反溶剂温度、搅拌速度、溶液浓度、喷嘴直径等6个工艺参数作为模型的输入变量，采用粒度作为输出变量。预测结果与实验值吻合较好，并将模拟数据与爆炸再结晶实验的实际数据进行了比较，发现模型的精度在不可接受的范围内，最大绝对百分比误差为11.52%。采用NASAS工艺制备的超细CL-20用于击雷管。CL-20基雷管起爆电压阈值在0.9 kV范围内，标准差为±0.1 kV。现有炸药的物理性质，如晶体粒度、形状、形态、晶体缺陷、纯度和晶间空隙的微观结构可以改变。有多种工艺可用于调整含能材料的粒径和形貌，如溶剂/非溶剂重结晶[1]、亚微米含能材料的连续结晶[2]、喷雾闪蒸[3]等。Yang等[4]采用溶剂/反溶剂法，通过喷嘴将溶液雾化成小液滴，与非溶剂流快速碰撞，得到粒径约为60 nm的纳米otatb。需要数学模型来预测颗粒特性随工艺参数的变化，为基于计算机的过程控制系统提供依据。Shallu Gupta等[5,6]采用微喷嘴辅助喷涂工艺(MNASP)对亚微米己硝基二苯乙烯(sm-HNS)炸药进行再结晶。利用分析网络过程(ANP)的加权平均技术对工艺属性进行优化。基于神经网络的爆炸激波和高应变率现象的优势材料研究论坛LLC材料研究进展13 (2019)121-127 https://doi.org/10.21741/9781644900338-21 122技术包括极限计算，强大的记忆和从实验数据中快速学习。此外，即使不完全了解输入参数的相互作用，它也可以准确地预测输出参数[7,8]。人工神经网络(ANN)和多层感知器(MLP)在人工智能(AI)研究中被广泛建立，其中输入和输出参数之间的非线性映射需要函数逼近[9,10]。Pannier等人解释了模糊逻辑(FL)建模、模糊集、隶属函数和模糊聚类的应用和一般特征[11]。神经模糊建模的理论细节可以在[12,13]中找到。然而，神经模糊建模所采用的方法即ANFIS的相关特征和背景[14]。从文献中可以看出，尽管ANFIS是一种强大的建模工具，但在炸药重结晶过程的研究中还没有使用到ANFIS。基于自适应网络的模糊推理系统(ANFIS)是一种将模糊系统与神经网络相结合的神经模糊技术，它利用了神经网络的学习特性和模糊系统的决策能力。本研究采用ANFIS模型对CL-20炸药在溶剂-抗溶剂重结晶过程中的粒径进行预测。本研究使用的炸药原料为ε-CL-20，粒径范围为50 ~ 60 μm。在本研究工作中，为制备UF-CL20，设计、开发、制造和安装了喷嘴辅助溶剂-抗溶剂(NASAS)工艺，原理图如图2所示。为了制造UF-CL20炸药，采用了nasa的工艺进行了49次实验。 在实验设计的基础上，考虑了影响再结晶炸药输出的6个输入参数，即粒度。输入参数为溶液压力、反溶剂压力、反溶剂温度、搅拌速度、溶液浓度和喷嘴直径。输出参数即粒径作为响应变量。nasa工艺获得的UF-CL20的特性如下节所述。图1所示。相似条件下部分样品的粒径分布如图3所示，其中UF-CL20的平均粒径为2.61 μm，标准差为0.242 μm。共进行42次实验，记录ANFIS模型的42对输入-输出变量数据，如表1所示。采用XRD分析对再结晶的超细CL-20进行表征，以确保其结晶性，XRD谱图显示其衍射角与CL20相似，在19.98 2θ处有一个独特的不重叠衍射峰，如图4所示。进行FTIR分析，确保处理后的分子结构无变化，如图5所示。SEM照片显示，颗粒尺寸减小，形貌为爆炸激波和高应变率现象Materials Research Forum LLC Materials Research Proceedings 13 (2019) 121-127 https://doi.org/10.21741/9781644900338-21 123也受工艺参数的影响，如图6所示。形状是多面体和近球面几何形状的混合。表面似乎很光滑，缺陷/裂缝可以忽略不计。图2。粒径分布图3。处理后CL20的XRD图4。红外光谱分析图5。SEM显微照片粒径实验数据运行顺序实验溶液压力(bar)反溶剂压力(bar)反溶剂温度(℃)搅拌转速(RPM)溶液浓度(%)喷嘴直径(mm)粒径(μm) 1 n -19 6 6 -9 800 5 0.7 5.63 2 n -20 77 -9 800 5 0.7 5.77 3 n - 26a 5 1 3
{"title":"ANFIS Modeling for Prediction of Particle Size in Nozzle Assisted Solvent-Antisolvent Process for Making Ultrafine CL-20 Explosiv","authors":"D. Pal, Shallu Gupta, D. Jindal, A. Kumar, A. Aggarwal, P. Lata","doi":"10.21741/9781644900338-21","DOIUrl":"https://doi.org/10.21741/9781644900338-21","url":null,"abstract":"Physical properties such as particle size, surface area and shape of explosive control the rapidity and reliability of initiation, and detonation and thus determine the performance of an explosive device such as slapper detonators. In this paper, Nozzle assisted solvent/antisolvent (NASAS) process for recrystallisation of CL-20 explosive is established. Many process parameters are involved which affect the particle size of the explosive. Therefore an accurate prediction of particle size is required to tailor the particle size. In the present work, an intelligent algorithm is applied to build a simplified relationship between recrystallization process parameters and particle size. This can be used to predict explosive particle size with a wide range of process parameters through an adaptive neuro-fuzzy inference system (ANFIS). The model is trained using experimental data obtained from design of experiment techniques utilizing a MATLAB software. Six process parameters such as Solution pressure, Antisolvent pressure, Antisolvent temperature, Stirrer speed, Solution concentration and Nozzle diameter are used as input variables of the model and the particle size is used as the output variable. The predicted results are in close agreement with experimental values and the accuracy of the model has been tested by comparing the simulated data with actual data from the explosive recrystallization experiments and found to be inacceptable range with maximum absolute percentage error of 11.52 %. The ultrafine CL-20 prepared by NASAS process is used in Slapper detonator application. The threshold initiation voltages for CL-20 based slapper detonator is found to be in the range of 0.9 kV with standard deviation of ±0.1 kV. Introduction The physical properties such as crystal particle size, shape, morphology, crystalline imperfections, purity and microstructure of the inter-crystalline voids of an existing explosive can be altered. There are wide variety of processes available for tailoring particle size and morphology of energetic materials such as solvent/non-solvent recrystallization[1],continuous crystallization of submicrometer energetic materials [2], spray flash evaporation [3]Yang et al. [4] obtained nanoTATB by using solvent/anti-solvent method with a particle size of 60 nm approximately through atomization of solution by a nozzle to small droplets and colliding rapidly with non-solvent flow. There is a need of mathematical model to predict particle characteristics as a function of process parameters to provide a basis for a computer based process control system. Shallu Gupta et al.[5,6], used micro nozzle assisted spraying process (MNASP) for recrystallization of Submicrometer Hexanitrostilbene (sm-HNS) Explosive. The process attributes were optimized using weighted average techniques of Analytical Network Process (ANP). The advantages of neural network based Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials R","PeriodicalId":415881,"journal":{"name":"Explosion Shock Waves and High Strain Rate Phenomena","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123471151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.21741/9781644900338-10
T. Matsuishi, F. Kawashima, H. Oda, K. Fujiwara
There are many things in our surroundings that are at risk of explosion (e.g. lithium ion batteries, power modules, spray cans etc.), and there is a possibility of causing great damage to the surroundings due to explosive fragments. For safe operation of them, it is essential to establish a way to protect the surroundings from explosive fragments. In this study, the purpose is to develop a compact container protecting the surroundings from explosive fragments. UltraHigh Molecular Weight polyethylene (UHMW) which is excellent in strength against explosive and penetrationof fragments was used for container, and Dyneema string or Zylon string were wound around the container for suppressing deformation. In order to observe a deformation of containers due to explosion, containers were blown up by explosives, and taken by high speed camera. Experimental results showed that the supporting strings are available for suppressing deformation. Introduction It is expected that power modules will be popularized due to the influence of smart grid and soon, but when dielectric breakdown occurs when high voltage exceeding breakdown voltage is applied, explosion occurs due to high heat of chip of component parts have been confirmed. Besides, there are many things that have a risk of explosion around us, such as lithium ion batteries used in smart phones, headphones, etc. and spray cans used in paints, insecticides, etc. Because of the possibility of damage to the surrounding people and things due to the explosion and the fragments of the explosive component parts, it is essential to establish a method to protect the surroundings from explosion and fragments in order to operate safely. As a method of protecting the surroundings from explosion and fragments, it is conceivable to develop a container that has strength against explosion and penetration. Strength against shock and high speed penetration of fragments is required for the material of the container. And also, in the case of lithium ion batteries or power modules, containers should be lightweight and compact to incorporate into the equipment in which they are used. As a material of container, UHMW which satisfies the above properties was used for container. Also, UHMW was reinforced by Dyneema string or Zylon string protecting from being broken due to an increase in strain. In order to investigate the influence of penetration of fragments, explosives were loaded in metal pipes and placed inside the container and blown up. High speed deformation due to explosion was observed by high speed camera. It was also investigated whether Dyneema and Zylon can be used as the material of the reinforcing layer. Experiments were conducted in Shock Wave Laboratory, Kumamoto University, Japan. Explosion experiment of UHMW1 The deformation of UHMW due to explosion was observed. Sizes of UHMW used in the experiment and a schematic diagram of the experimental device are shown in Fig.1, and the Explosion Shock Waves and High St
{"title":"Development of a Compact Container Protecting from Accidental Explosions of High Energy Materials","authors":"T. Matsuishi, F. Kawashima, H. Oda, K. Fujiwara","doi":"10.21741/9781644900338-10","DOIUrl":"https://doi.org/10.21741/9781644900338-10","url":null,"abstract":"There are many things in our surroundings that are at risk of explosion (e.g. lithium ion batteries, power modules, spray cans etc.), and there is a possibility of causing great damage to the surroundings due to explosive fragments. For safe operation of them, it is essential to establish a way to protect the surroundings from explosive fragments. In this study, the purpose is to develop a compact container protecting the surroundings from explosive fragments. UltraHigh Molecular Weight polyethylene (UHMW) which is excellent in strength against explosive and penetrationof fragments was used for container, and Dyneema string or Zylon string were wound around the container for suppressing deformation. In order to observe a deformation of containers due to explosion, containers were blown up by explosives, and taken by high speed camera. Experimental results showed that the supporting strings are available for suppressing deformation. Introduction It is expected that power modules will be popularized due to the influence of smart grid and soon, but when dielectric breakdown occurs when high voltage exceeding breakdown voltage is applied, explosion occurs due to high heat of chip of component parts have been confirmed. Besides, there are many things that have a risk of explosion around us, such as lithium ion batteries used in smart phones, headphones, etc. and spray cans used in paints, insecticides, etc. Because of the possibility of damage to the surrounding people and things due to the explosion and the fragments of the explosive component parts, it is essential to establish a method to protect the surroundings from explosion and fragments in order to operate safely. As a method of protecting the surroundings from explosion and fragments, it is conceivable to develop a container that has strength against explosion and penetration. Strength against shock and high speed penetration of fragments is required for the material of the container. And also, in the case of lithium ion batteries or power modules, containers should be lightweight and compact to incorporate into the equipment in which they are used. As a material of container, UHMW which satisfies the above properties was used for container. Also, UHMW was reinforced by Dyneema string or Zylon string protecting from being broken due to an increase in strain. In order to investigate the influence of penetration of fragments, explosives were loaded in metal pipes and placed inside the container and blown up. High speed deformation due to explosion was observed by high speed camera. It was also investigated whether Dyneema and Zylon can be used as the material of the reinforcing layer. Experiments were conducted in Shock Wave Laboratory, Kumamoto University, Japan. Explosion experiment of UHMW1 The deformation of UHMW due to explosion was observed. Sizes of UHMW used in the experiment and a schematic diagram of the experimental device are shown in Fig.1, and the Explosion Shock Waves and High St","PeriodicalId":415881,"journal":{"name":"Explosion Shock Waves and High Strain Rate Phenomena","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117140528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.21741/9781644900338-23
M. Kumar, Y. Singh, P. Kumar
Shaped charge warheads are being utilized in defence applications against a wide variety of targets provided by armour, RCC and soil cover. Shaped charge warhead focus the explosive energy by the use of a cavity lined with metal normally called a liner. The concentration of energy along the axis of the warhead acts as force multiplier and hence lighter warheads are possible for deeper penetration. Performance of the shaped charge warhead is function of jet tip velocity, jet length and break up time (BUT). These performance parameters are greatly influenced by liner geometry, liner thickness and liner cone angle and selection of explosive. In this paper, simulations using AUTODYN numerical hydrocode were carried out to study the effect of liner geometry (Tulip vs conical), liner cone angle (50,60,70,80) and liner thickness(4mm,6mm,8mm,10mm and 12mm) on large caliber shaped charge warheads. Numerical simulations were also done to study the effect of wave shaper in shaped charge warhead. A shaped charge warhead of dia.340mm has been designed by using AUTODYN numerical hydrocode. OFE Copper (ASTM B152 C10100) is used as liner material. A wave shaper of dia.210mm and nylon material was used in shaped charge warhead. An Eulerian approach was used for the liner, casing, wave shaper and explosive parts. A single point initiation in the centre of the rear end of warhead was chosen. The numerical simulation results showed that the jettip velocity decreases in between 15-20% of liner position with increasing the cone angle when the other parameters are the same. For the cone angle 60, jet tip-velocity decreases as liner thickness is increased from 4mm (Vj-tip : 8.14 km/s) to 12mm (Vj-tip : 6.7 km/s). It was also realized that in case of wave shaper warhead there is more than 15% increase in jet tip velocity and 10% increase in jet length in comparison to without wave shaper warhead due to increase in collapse velocity of liner elements. The slug velocity is 1.22km/s in case of with wave shaper warhead whereas it was 1.05 km/s in without wave shaper. It means that a decision for the selection of liner geometry and dimensions of a shaped charge penetrator should be done according to target, required desired effect on target, permissible weight and available space for the warhead.
{"title":"Effect of Liner Cone Angle, Liner Thickness and Wave Shaper in Large Caliber Shaped Charge Warheads","authors":"M. Kumar, Y. Singh, P. Kumar","doi":"10.21741/9781644900338-23","DOIUrl":"https://doi.org/10.21741/9781644900338-23","url":null,"abstract":"Shaped charge warheads are being utilized in defence applications against a wide variety of targets provided by armour, RCC and soil cover. Shaped charge warhead focus the explosive energy by the use of a cavity lined with metal normally called a liner. The concentration of energy along the axis of the warhead acts as force multiplier and hence lighter warheads are possible for deeper penetration. Performance of the shaped charge warhead is function of jet tip velocity, jet length and break up time (BUT). These performance parameters are greatly influenced by liner geometry, liner thickness and liner cone angle and selection of explosive. In this paper, simulations using AUTODYN numerical hydrocode were carried out to study the effect of liner geometry (Tulip vs conical), liner cone angle (50,60,70,80) and liner thickness(4mm,6mm,8mm,10mm and 12mm) on large caliber shaped charge warheads. Numerical simulations were also done to study the effect of wave shaper in shaped charge warhead. A shaped charge warhead of dia.340mm has been designed by using AUTODYN numerical hydrocode. OFE Copper (ASTM B152 C10100) is used as liner material. A wave shaper of dia.210mm and nylon material was used in shaped charge warhead. An Eulerian approach was used for the liner, casing, wave shaper and explosive parts. A single point initiation in the centre of the rear end of warhead was chosen. The numerical simulation results showed that the jettip velocity decreases in between 15-20% of liner position with increasing the cone angle when the other parameters are the same. For the cone angle 60, jet tip-velocity decreases as liner thickness is increased from 4mm (Vj-tip : 8.14 km/s) to 12mm (Vj-tip : 6.7 km/s). It was also realized that in case of wave shaper warhead there is more than 15% increase in jet tip velocity and 10% increase in jet length in comparison to without wave shaper warhead due to increase in collapse velocity of liner elements. The slug velocity is 1.22km/s in case of with wave shaper warhead whereas it was 1.05 km/s in without wave shaper. It means that a decision for the selection of liner geometry and dimensions of a shaped charge penetrator should be done according to target, required desired effect on target, permissible weight and available space for the warhead.","PeriodicalId":415881,"journal":{"name":"Explosion Shock Waves and High Strain Rate Phenomena","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128331228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.21741/9781644900338-12
A. Takao, R. Tomoshige, A. Kira
In explosive welding, the velocity of flyer plate requisite for joining of two different kinds of metallic sheet is several hundred meters per second. We thought that the velocity would be accomplished easily without explosives. A lightweight projectile, which receives higher pressure on the rear side than front side, goes forward and is accelerated to extremely high velocity, even if the pressure difference is small. Joining should be achieved, when a thin metal sheet attached on the front of the projectile collides with another metal plate fixed on an oblique block. Oblique collisions between several kinds of metal were examined. Examinations of the joint interfaces of this resultant by both scanning electron and optical microscopes find no opening. Detachment at the joint interface did not occur, when tensile forces were applied. Therefore, we regard that the joint interface has sufficient strength. Introduction High-energy-rate processing has many excellent features that differ from static processing. For example, explosive welding, which is one of the methods for producing cladding materials, is applied to combinations in dissimilar metals and non-metals that are difficult to bond in diffusion bonding. Metal processing and material synthesis have been carried out with shock waves generated by explosives [1, 2]. The method that does not use explosives was originated, as experiments using explosives require qualifications to handle them and the cost of the experiment is high. The general methods of joining metals are mechanical bonding, metallurgical bonding, and chemical bonding. Each has advantages and disadvantages, and it is necessary to select a bonding method suitable for the material and bonding conditions to join metals efficiently. Explosive welding has the best features among these bonding methods. A simple projectile accelerator using a difference in air pressure has been produced. The equivalent qualifications to explosive welding will be succeeded, if the device were used. When this device is applied to sheet metal forming, good results than expected was obtained. Then I tried joining of dissimilar metals. Experiment In explosive welding, the flyer plate is arranged in parallel with an appropriate distance from the parent plate, and one end of the explosive placed on the flyer plate is detonated. In the proposed method, the flyer plate is accelerated by the air pressure difference substitute for the explosive. Since a high pressure difference is required to obtain a large acceleration, a vacuum collision chamber and a high-pressure chamber are made. Figure 1 is a photograph of the overall view of the projectile accelerator. A metal plate attached to the flyer plate is accelerated by the pressure Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 69-73 https://doi.org/10.21741/9781644900338-12 70 difference, and it collides with another metal plate at high spee
{"title":"Joining of Dissimilar Metals Using Low Pressure Difference","authors":"A. Takao, R. Tomoshige, A. Kira","doi":"10.21741/9781644900338-12","DOIUrl":"https://doi.org/10.21741/9781644900338-12","url":null,"abstract":"In explosive welding, the velocity of flyer plate requisite for joining of two different kinds of metallic sheet is several hundred meters per second. We thought that the velocity would be accomplished easily without explosives. A lightweight projectile, which receives higher pressure on the rear side than front side, goes forward and is accelerated to extremely high velocity, even if the pressure difference is small. Joining should be achieved, when a thin metal sheet attached on the front of the projectile collides with another metal plate fixed on an oblique block. Oblique collisions between several kinds of metal were examined. Examinations of the joint interfaces of this resultant by both scanning electron and optical microscopes find no opening. Detachment at the joint interface did not occur, when tensile forces were applied. Therefore, we regard that the joint interface has sufficient strength. Introduction High-energy-rate processing has many excellent features that differ from static processing. For example, explosive welding, which is one of the methods for producing cladding materials, is applied to combinations in dissimilar metals and non-metals that are difficult to bond in diffusion bonding. Metal processing and material synthesis have been carried out with shock waves generated by explosives [1, 2]. The method that does not use explosives was originated, as experiments using explosives require qualifications to handle them and the cost of the experiment is high. The general methods of joining metals are mechanical bonding, metallurgical bonding, and chemical bonding. Each has advantages and disadvantages, and it is necessary to select a bonding method suitable for the material and bonding conditions to join metals efficiently. Explosive welding has the best features among these bonding methods. A simple projectile accelerator using a difference in air pressure has been produced. The equivalent qualifications to explosive welding will be succeeded, if the device were used. When this device is applied to sheet metal forming, good results than expected was obtained. Then I tried joining of dissimilar metals. Experiment In explosive welding, the flyer plate is arranged in parallel with an appropriate distance from the parent plate, and one end of the explosive placed on the flyer plate is detonated. In the proposed method, the flyer plate is accelerated by the air pressure difference substitute for the explosive. Since a high pressure difference is required to obtain a large acceleration, a vacuum collision chamber and a high-pressure chamber are made. Figure 1 is a photograph of the overall view of the projectile accelerator. A metal plate attached to the flyer plate is accelerated by the pressure Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 69-73 https://doi.org/10.21741/9781644900338-12 70 difference, and it collides with another metal plate at high spee","PeriodicalId":415881,"journal":{"name":"Explosion Shock Waves and High Strain Rate Phenomena","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116057807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.21741/9781644900338-27
S. Saravanan, K. Raghukandan, G. Murugan
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Pub Date : 1900-01-01DOI: 10.21741/9781644900338-25
Satyanarayan
In the present study, underwater explosive welding of commercial pure Sn and Al plates was attempted. Distance between the explosive and the center of the sample was varied to change the pressure applied to the plates to be welded. Evolution of interfacial microstructures at the welded Sn/Al joints was assessed. An increase in the distance between explosive and the sample exhibited decrease in the formation of wavy morphology at the interface. Cross−sectional interfacial microstructures clearly indicated that, Sn and Al plates can be joined successfully using underwater explosive welding technique. Introduction The Explosive welding (EXW) is a solid state process used for the joining (metallurgical) of similar or dissimilar a metal which is regarded as one of the most widely employed materials processing technique [1]. The EXW is generally performed in an open atmosphere. However, it is reported that conventional explosive welding always poses a problem for welding of materials, particularly for thin metal plate (below 1mm thickness) as well as brittle materials such as amorphous ribbon/ceramics and fusing of tungsten (W)/Cu [2,3]. Literature suggested that by using underwater explosive welding a significant decrease in kinetic energy (K.E) loss at the interface of flyer plate and base plate can be achieved [4−6]. In this method, water acts as a pressure transmitting medium. The underwater shock waves prevent the distortion of the welded joint and ensure the integrity of the joints. Hence, underwater explosive welding is regarded as one of the best and novel welding techniques [7, 8]. It reported that, Al/Steel, Al/Cu, Sn/Cu and Cu/Stainless Steel combinations of materials are the most essential in the electrical engineering and among these Al/Cu joints are widely used as electrical connectors in many industries because of their good corrosion resistance and electrical conductivity [9]. Although numerous investigations on explosive welding of various metal combinations were conducted by the researchers [9−12] welding and cladding of Sn and Al using this technique have not been paid attention. Sn based solder alloys are electrically connected with metallic components (most notably the Cu conductors) in the electronic device. However there is no solder alloy in electronic applications which operates with Al in the same way that ordinary solders operate with copper. Because Al does not alloy readily with solders, moreover the Al surface is covered with a thin invisible coating of aluminium oxide. Thin oxide film makes it difficult to join dissimilar materials [13]. Thus, the aim of current study is to make an attempt to fusing of Sn and Al plates using underwater explosive welding method. Further, evolution of interfacial microstructures between welded Sn/Al joint is investigated. Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 149-153 https://doi.org/10.21741/9781644900338-2
{"title":"Underwater Explosive Welding of Tin and Aluminium Plates","authors":"Satyanarayan","doi":"10.21741/9781644900338-25","DOIUrl":"https://doi.org/10.21741/9781644900338-25","url":null,"abstract":"In the present study, underwater explosive welding of commercial pure Sn and Al plates was attempted. Distance between the explosive and the center of the sample was varied to change the pressure applied to the plates to be welded. Evolution of interfacial microstructures at the welded Sn/Al joints was assessed. An increase in the distance between explosive and the sample exhibited decrease in the formation of wavy morphology at the interface. Cross−sectional interfacial microstructures clearly indicated that, Sn and Al plates can be joined successfully using underwater explosive welding technique. Introduction The Explosive welding (EXW) is a solid state process used for the joining (metallurgical) of similar or dissimilar a metal which is regarded as one of the most widely employed materials processing technique [1]. The EXW is generally performed in an open atmosphere. However, it is reported that conventional explosive welding always poses a problem for welding of materials, particularly for thin metal plate (below 1mm thickness) as well as brittle materials such as amorphous ribbon/ceramics and fusing of tungsten (W)/Cu [2,3]. Literature suggested that by using underwater explosive welding a significant decrease in kinetic energy (K.E) loss at the interface of flyer plate and base plate can be achieved [4−6]. In this method, water acts as a pressure transmitting medium. The underwater shock waves prevent the distortion of the welded joint and ensure the integrity of the joints. Hence, underwater explosive welding is regarded as one of the best and novel welding techniques [7, 8]. It reported that, Al/Steel, Al/Cu, Sn/Cu and Cu/Stainless Steel combinations of materials are the most essential in the electrical engineering and among these Al/Cu joints are widely used as electrical connectors in many industries because of their good corrosion resistance and electrical conductivity [9]. Although numerous investigations on explosive welding of various metal combinations were conducted by the researchers [9−12] welding and cladding of Sn and Al using this technique have not been paid attention. Sn based solder alloys are electrically connected with metallic components (most notably the Cu conductors) in the electronic device. However there is no solder alloy in electronic applications which operates with Al in the same way that ordinary solders operate with copper. Because Al does not alloy readily with solders, moreover the Al surface is covered with a thin invisible coating of aluminium oxide. Thin oxide film makes it difficult to join dissimilar materials [13]. Thus, the aim of current study is to make an attempt to fusing of Sn and Al plates using underwater explosive welding method. Further, evolution of interfacial microstructures between welded Sn/Al joint is investigated. Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 149-153 https://doi.org/10.21741/9781644900338-2","PeriodicalId":415881,"journal":{"name":"Explosion Shock Waves and High Strain Rate Phenomena","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128177345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.21741/9781644900338-3
A. Mamalis
Trends and developments in advanced manufacturing of advanced materials from macroto nanoscale subjected to static, lowspeed / high speed / hypervelocity impact and shock loading, with sustainable industrial applications to net-shape manufacturing, bioengineering, transport, energy and environment, defense and safety, an outcome of the very extensive, over 50 years, work on these scientific and industrial areas performed by the author and his research international team, are briefly outlined. The impact of such advanced materials, manufacturing and loading techniques, products and applications on many technological areas, e.g. the manufacturing/machine tool sector, communications / data storage, transportations, health treatment, energy conservation, environmental and human-life protection, is significant and highly beneficial. Introduction The topics considered, an outcome of the very extensive academic and industrial work over 50 years on these fields performed by the author and his research international team, may be listed as: • Mechanics (Structural plasticity, Low / High speed impact loading, Hypervelocity impact, Shockwaves loading) • Precision / Ultraprecision manufacturing from macro-, microto nanoscale (Metal forming, Metal removal processing, Surface engineering / Wear, Non-conventional techniques) • Nanotechnology / Nanomaterials manufacturing • Ferrous and non-ferrous materials (Metals, Ceramics, Superhard, Polymers, Composites, Multifunctional), from macroto nanoscale (Nanostructured materials, Nanoparticles, Nanocomposites) • Powder production and processing technologies (High strain-rate phenomena and treatment under shock: Explosives, Electromagnetics, High temperature / high pressure techniques) • Biomechanics / Biomedical engineering • Transport / Crashworthiness of Vehicles: Passive and active safety for passengers and cargo (Surface transport: Automotive, Railway; Aeronautics: Aircraft, Helicopters) • Energy (Superconductors, Semiconductors, Electromagnetics, Solar cells, Photovoltaics, Nuclear reactors) • Environmental aspects (Impact on climate change: Nanotechnology; Automotive industry; Aeronautics industry) • Safety (Detection of explosives and hazardous materials) • Defense (Ballistics, Projectiles hitting targets, Shock loading) Explosion Shock Waves and High Strain Rate Phenomena Materials Research Forum LLC Materials Research Proceedings 13 (2019) 13-24 https://doi.org/10.21741/9781644900338-3 14 • Industrial sustainability Some trends and developments in Advanced Manufacturing from macroto nanoscale in the important engineering topics from industrial, research and academic point of view: nanotechnology, precision /ultraprecision engineering and advanced materials (metals, ceramics, polymeric, composites/nanocomposites) under static, low/high speed impact, hypervelocity impactand shock loading, with sustainable industrial applications to net-shape manufacturing, bioengineering, transport, energy/environment and defen
作者及其国际研究团队在这些科学和工业领域进行了50多年的广泛工作，简要概述了从宏观到纳米尺度的先进材料在静态、低速/高速/超高速冲击和冲击载荷下的先进制造的趋势和发展，以及在净形制造、生物工程、运输、能源和环境、国防和安全等领域的可持续工业应用。这种先进的材料、制造和装载技术、产品和应用对许多技术领域的影响是重大的和非常有益的，例如制造/机床部门、通信/数据存储、运输、健康治疗、节能、环境和人类生命保护。所考虑的主题是作者及其国际研究团队在这些领域进行了50多年广泛的学术和工业工作的结果，可以列出如下:•从宏观、微观到纳米尺度的精密/超精密制造(金属成形、金属去除加工、表面工程/磨损、非常规技术)•纳米技术/纳米材料制造•黑色金属和有色金属材料(金属、陶瓷、超硬、聚合物、复合材料、多功能)，从宏观到纳米尺度(纳米结构材料、•粉末生产和加工技术(高应变率现象和冲击处理:炸药、电磁、高温/高压技术)•生物力学/生物医学工程•运输/车辆耐撞性:乘客和货物的被动和主动安全(地面运输:汽车、铁路;•能源(超导体、半导体、电磁学、太阳能电池、光伏、核反应堆)•环境方面(对气候变化的影响:纳米技术;汽车工业;•安全(爆炸物和危险材料的检测)•国防(弹道学，射弹击中目标，冲击载荷)爆炸冲击波和高应变率现象材料研究论坛LLC材料研究进展13 (2019)13-24 https://doi.org/10.21741/9781644900338-3 14•工业可持续性先进制造的一些趋势和发展，从宏观到纳米尺度在工业，研究和学术观点:本次ESHP 2019特邀讲座简要概述了静态、低/高速、超高速冲击和冲击载荷下的纳米技术、精密/超精密工程和先进材料(金属、陶瓷、聚合物、复合材料/纳米复合材料)在净形制造、生物工程、交通、能源/环境和国防/安全等领域的可持续工业应用。先进制造技术的原理可以通过六个主要要素来确定，如图1所示，中心要素是对材料的强制变形，即加工本身，在考虑工具和工件之间的界面的情况下，引入润滑和摩擦、工具材料特性和部件表面完整性的跨学科特征。接收到的材料结构在变形加工过程中会发生严重的变化，从静态到非常高的应变率现象/冲击载荷，因此，加工前后的材料测试和质量控制是力学、制造和材料科学家感兴趣的主要领域。机床的性能以及工具设计也非常重要，同时，如今，技术经济方面，如制造系统的概念，例如自动化，建模和仿真，快速原型，工艺规划，计算机集成制造，节能和回收，以及环境方面在先进制造工程中很重要[1]。图1先进制造技术原理爆炸激波与高应变率现象Materials Research Forum LLC Materials Research Proceedings 13 (2019) 13-24 https://doi.org/10.21741/9781644900338-3 15控制材料变形的结构塑性力学如图2所示，主要与[1,2]相关:(a)金属、聚合物和复合材料的低应变率现象，即静态、低速冲击载荷下的变形，见图2(i)。在这种情况下，材料的性能表现为其应力-应变曲线。延展性金属和聚合物随着固定和移动塑料铰链的形成而发生塑性变形。 与这种延性机制相反，脆性复合材料的变形机制是通过材料破碎实现的，形成广泛的微裂过程，易于控制，并且取决于纤维和树脂的性能和纤维的取向。图2结构塑性力学(b)金属、陶瓷和超硬材料(金刚石、CBN)的高应变率现象，即在高速/超高速冲击(冲击波载荷)下的变形，见图2(ii)。在动/冲击加载过程中，产生了具有真实冲击波剖面(压力，P vs时间，t)的纵向P冲击波，并以高速进入机体，根据材料在冲击条件下的相应状态计算，即其Hugoniot曲线(压力，P比体积，V关系)，定义为所有冲击状态的轨迹，本质上描述了材料的特性。颗粒以高速加速进入孔隙，相互碰撞，导致颗粒表面上某一点受到射流冲击而形成剪切s波，在颗粒内部传播并在颗粒表面反射，由于剥落而形成射流，随后已经形成的射流在颗粒间空隙中以与激波相同的方向移动。摩擦能释放结果，爆炸激波和高应变率现象材料研究论坛LLC材料研究进展13 (2019)13-24 https://doi.org/10.21741/9781644900338-3 16因此，在表面区域熔化与相关键合一旦材料凝固。在脆性材料的固结过程中，也会发生颗粒断裂，导致空隙的填充，同时也可以添加活性元素来帮助粘结过程。高压状态产生了大量的晶格缺陷和位错亚结构，经常导致局部剪切和微裂纹。冲击波的能量耗散模式及其机制与冲击波释放能量有关，E = 1 / 2 P (V-V0)，其中P为峰值冲击压力，V0为初始粉末比体积，V为固体材料体积。制造零件的质量主要取决于其尺寸和形状精度、表面完整性和产品的功能特性。制造工程的发展与微型化趋势有关，并伴随着制造零件精度的不断提高。产品小型化的两个主要趋势是，见图3:•精密/超精密制造(金属成形、金属去除加工、表面工程/磨损、非常规技术)，见图3(i)，由高精度机床进行;•纳米技术加工，见图3(i)，即通过采用新的先进能量束工艺，允许原子操作，从而设计和制造纳米结构材料，使每个原子或分子在指定位置，并表现出新颖和显着改善的物理，化学，机械和电气性能，从而制造具有原子和/或分子尺度精度的设备。图3(ii)列出了纳米材料制造的各个阶段[3]。
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Pub Date : 1900-01-01DOI: 10.21741/9781644900338-14
H. Inokawa, K. Ishida, R. Tomoshige, K. Hokamoto, Shigeru Tanaka
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