On Study of Free Metal Forming Using Underwater Shock Wave

In the material processing such as shock synthesis and powder consolidation by shock waves the method for generating dynamic pressure is of very importance for the final recovered materials. A general and convenient way for producing shock wave needed in such field is to take advantage of the explosion effect from high explosive. Therefore, it becomes an interest subject how to produce dynamic pressure as high as possible under the given high explosive. Starting from this motivation, we put forward a method of high-pressure generation by using the overdriven detonation of high explosive. The basic configuration for this device is summarized in the following. A metal flyer accelerated by the high explosive is used to impact another layer of high explosive to incur an overdriven detonation in this layer of explosive. The overdriven detonation of high explosive acts on the powder materials, providing the high dynamic pressure for it. To examine the efficiency of this combination, a numerical computation is performed to this system. The details on the illustration of this system and numerical treatment will be given.

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A Method for Producing Extra-High Dynamic Pressure Due to the Efficient Use of High Explosive

Journal of Pressure Vessel Technology ◽

10.1115/1.1687384 ◽

2004 ◽

Vol 126 (2) ◽

pp. 264-268 ◽

Cited By ~ 2

Author(s):

Zhi-Yue Liu ◽

Katsumi Tanaka ◽

Shigeru Itoh

Keyword(s):

Shock Wave ◽

High Explosive ◽

Dynamic Pressure ◽

Powder Materials ◽

Powder Consolidation ◽

High Dynamic Pressure ◽

High Dynamic ◽

Overdriven Detonation ◽

Vital Factor

In the material processing such as shock synthesis and powder consolidation by shock waves the method for generating dynamic pressure is a vital factor for the quality of the final recovered materials. A general and convenient way for producing shock wave demanded in such applications is to take advantage of the explosion effect from high explosive. Under normal conditions, a given high explosive can only provide some kind of magnitude of dynamic pressure after its explosion. Therefore, it is whether possible to obtain the higher dynamic pressure by adequately changing the form of the explosion of high explosive. Starting from this motivation, we put forward a new method for producing high dynamic pressure from the use of the overdriven detonation of high explosive. The proposed device consists of the following configurations. A metal flyer accelerated by the high explosive is used to impact another layer of high explosive to incur an overdriven detonation in this layer of explosive. The overdriven detonation of high explosive acts on the powder materials, bringing out high dynamic pressures to the materials studied. To examine the efficiency of this combination on the improvement of dynamic pressure, a numerical computation is performed on this system. The details on the illustration of this method as well as the results of numerical investigation will be given.

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Food Processing Trials Using Underwater Shock Wave by Electrical Discharge

Materials Science Forum ◽

10.4028/www.scientific.net/msf.767.223 ◽

2013 ◽

Vol 767 ◽

pp. 223-228 ◽

Cited By ~ 3

Author(s):

Seisaku Iwasa ◽

Hironori Maehara ◽

Masatoshi Nishi ◽

Shigeru Tanaka ◽

Toshiaki Watanabe ◽

...

Keyword(s):

Shock Wave ◽

Cold Water ◽

Dynamic Pressure ◽

New Method ◽

Underwater Shock Wave ◽

Running Water ◽

Wire Explosion ◽

Frozen Food ◽

Underwater Shock ◽

High Dynamic

We propose a new method for the efficient decompression of frozen food under high dynamic pressure. Two experiments are conducted on an ice block containing peeled shrimp: wire explosion and underwater shock wave. In these experiments, the ice is finely crushed, while the frozen peeled shrimps retain their original shape and can be efficiently extracted. Since ice crushing is performed momentarily, the defrosting time is significantly shorter than that in traditional thawing techniques, such as melting in running water or cold-water soaking. This new method could increase the efficiency of food production processes.

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A Study on the Powder Consolidation of Metal Powder for Magnetic Material Using Underwater Shock Wave

Volume 4: Fluid Structure Interaction, Parts A and B ◽

10.1115/pvp2006-icpvt-11-93347 ◽

2006 ◽

Cited By ~ 1

Author(s):

Kazuhiro Kawano ◽

Young Kook Kim ◽

Hideki Hamashima ◽

Shigeru Itoh

Keyword(s):

Magnetic Material ◽

Shock Wave ◽

High Pressure ◽

Numerical Analysis ◽

Heating System ◽

Metal Powders ◽

Underwater Shock Wave ◽

Powder Consolidation ◽

Shock Compaction ◽

Underwater Shock

In order to consolidate metal powders, the present investigation uses a shock wave derived from the detonation of an explosive and it’s called a shock compaction method. In the present investigation, we employed an ultra-high pressure generation device in order to generate underwater shock wave. The underwater shock wave is derived from the detonation wave in a water container and after that underwater shock wave is converged in the central axis. Finally, the high pressure of underwater shock wave is uniformly impinged on the powders. In case of experimental data that is measured by manganin gauge, the peak pressure of underwater shock wave is 16.8GPa, the result of numerical analysis is 17.9GPa. Considering for the measurement error (1GPa), it seems to be good agreement between the result of numerical analysis and experiment. Nd-Fe-B magnetic material powders are tried to consolidate using the assembly under optional temperatures by heating system and the samples recovered under different conditions were examined in terms of magnetic properties.

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Comparison of underwater shock wave attenuation of a new insensitive high explosive with different explosives

Combustion Explosion and Shock Waves ◽

10.1134/s0010508211060153 ◽

2011 ◽

Vol 47 (6) ◽

pp. 721-726 ◽

Cited By ~ 8

Author(s):

Lin Zhou ◽

Zhongyuan Xie ◽

Xuexia Wei

Keyword(s):

Shock Wave ◽

Wave Attenuation ◽

High Explosive ◽

Underwater Shock Wave ◽

Shock Wave Attenuation ◽

Underwater Shock

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Research on the Powder Consolidation by Using Shock Compaction Method

ASME 2010 Pressure Vessels and Piping Conference: Volume 4 ◽

10.1115/pvp2010-25151 ◽

2010 ◽

Author(s):

Keijiro Nishi ◽

Makoto Ide ◽

Nozomi Terasawa ◽

Seiichi Irie ◽

Shigeru Itoh

Keyword(s):

Thermal Conductivity ◽

Shock Wave ◽

Composite Material ◽

Particle Surface ◽

Copper Matrix ◽

Underwater Shock Wave ◽

Powder Consolidation ◽

Shock Compaction ◽

Underwater Shock ◽

Diamond Powders

Shock compaction of powder by using an underwater shock wave is studied and the technical advantages are reported. In this research, we propose a technique for shock compaction of copper/diamond powders by using an underwater shock wave generated by the detonation of explosive. This process produces a composite material in which the particles are strongly bonded due to melting caused by strong deformation and rapid solidification at the particle surface. The improvement of the thermal conductivity of the composite material collected is expected, because the diamond has a high thermal conductivity. Good compacts of composite materials in which diamond particles were dispersed in the copper matrix were obtained in this experiment, and their microstructures and thermal properties were examined. Moreover, pressure measurements and numerical calculations were performed to assess the effect of the pressuring condition in the explosive container.

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Shock Wave Propagation Inside of Pressure Vessel Used for Food Processing

Volume 4: Fluid-Structure Interaction ◽

10.1115/pvp2012-78292 ◽

2012 ◽

Cited By ~ 1

Author(s):

Hirofumi Iyama ◽

Yoshikazu Higa ◽

Shigeru Itoh

Keyword(s):

Numerical Simulation ◽

Shock Wave ◽

Wave Propagation ◽

Pressure Vessel ◽

Food Processing ◽

High Explosive ◽

Underwater Explosion ◽

Underwater Shock Wave ◽

Reflected Wave ◽

Underwater Shock

In this study, it has aimed at the design of the pressure vessel for food processing using an underwater shock wave. This study aims at the design of a pressure vessel in which the underwater shock wave generated by the underwater explosion of high explosive was experimentally investigated by the optical observation and the pressure measurement. Therefore the pressure vessel is designed so that suitable pressure may apply on food. This designed vessel is evaluated by the numerical simulation. The interaction of the underwater shock wave, the incident wave and the reflected wave are investigated by the numerical simulation.

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Basics of Explosive Welding Process and Some Examples Using Underwater Shock Wave

JOURNAL OF THE JAPAN WELDING SOCIETY ◽

10.2207/jjws.87.43 ◽

2018 ◽

Vol 87 (1) ◽

pp. 43-47

Author(s):

Kazuyuki HOKAMOTO

Keyword(s):

Shock Wave ◽

Explosive Welding ◽

Welding Process ◽

Underwater Shock Wave ◽

Underwater Shock

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Explosive Welding Using Underwater Shock Wave Generated by the Detonation of the Detonating Code

Materials Science Forum ◽

10.4028/www.scientific.net/msf.673.265 ◽

2011 ◽

Vol 673 ◽

pp. 265-270 ◽

Cited By ~ 3

Author(s):

Akihisa Mori ◽

Li Qun Ruan ◽

Kazumasa Shiramoto ◽

Masahiro Fujita

Keyword(s):

Shock Wave ◽

Sound Velocity ◽

Detonation Velocity ◽

Explosive Welding ◽

New Method ◽

Underwater Shock Wave ◽

Metal Plates ◽

Experimental Parameters ◽

Underwater Shock ◽

Point Velocity

Detonating code is a flexible code with an explosive core. It is used to transmit the ignition of explosives with high detonation velocity in the range of 5.5 to 7 km/s. However, it is difficult to use detonating code for the explosive welding of common metals since the horizontal point velocity usually exceeds the sound velocity. Hence, in the present work, a new method using underwater shock wave generated by the detonation of detonating code was tried. The details of the experimental parameters and the results are presented. From the results it is observed that the above technique is suitable to weld thin metal plates with relatively less explosives.

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