The Experts below are selected from a list of 150 Experts worldwide ranked by ideXlab platform
Shigeru Itoh - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation on manufacturing of pressure vessel for shock food processing using Explosive Forming
Volume 4: Fluid-Structure Interaction, 2016Co-Authors: Hirofumi Iyama, Masatoshi Nishi, Yoshikazu Higa, Ken Shimojima, Osamu Higa, Shigeru ItohAbstract:The Explosive Forming is a characteristic Forming method. An underwater shock wave is generated by underwater explosion of the Explosive. A metal plate is affected high strain rate by the shock loading and is formed along a metal die. Although this method has the advantage of mirroring the shape of the die, a free Forming was used in this paper. An expensive metal die is not necessary for this free Forming. It is possible that a metal plate is formed with simple supporting parts. However, the Forming shape is depend on the shock pressure distribution act on the metal plate. This pressure distribution is able to change by the shape of Explosive, a mass of Explosive and a shape of pressure vessel. On the other hand, we need the pressure vessel for food processing by the underwater shock wave. Therefore, we propose making the pressure vessel by the Explosive Forming. One design suggestion of pressure vessel made of stainless steel was considered. However, we cannot decide suitable conditions, the mass of the Explosive and the distance between the Explosive and the metal plate to make the pressure vessel. In order to decide these conditions, we have tried the numerical simulation of this Explosive Forming. The basic simulation method was ALE (Arbitrary Laglangian Eulerian) method. Mie-Grümeisen EOS (equation of state), JWL EOS, Johnson-Cook constitutive equation for a material model were applied in the numerical simulation. In this paper, the underwater pressure contours to clear the propagations of the underwater shock wave, Forming processes and deformation velocity of the metal plate is shown and it will be discussed about those results.
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Study on the Effects of Shock Wave Propagation on Explosive Forming
Materials Science Forum, 2013Co-Authors: Hirofumi Iyama, Yoshikazu Higa, Shigeru ItohAbstract:Explosive Forming is one of the unconventional techniques, in which, most commonly, the water is used as the pressure transmission medium. The Explosive is set at the top of the pressure vessel filled with water, and is detonated by an electric detonator. The underwater shock wave propagates through the water medium and impinges on the metal plate, which in turn, deforms. There is another pressure pulse acting on the metal plate as the secondary by product of the expansion of the gas generated by detonation of Explosive. The secondary pressure pulse duration is longer and the peak pressure is lower than the primary shock pressure. However, the intensity of these pressure pulse is based also on the conditions of a pressure vessel. In order to understand the effects of the configuration of the pressure vessel on the deformation of a metal plate, numerical simulation was performed. This paper reports those results.
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Study on Explosive Forming of Aluminum Alloy
The International Journal of Multiphysics, 2010Co-Authors: Hirofumi Iyama, Shigeru ItohAbstract:Now, the aluminum alloy is often used as auto parts, for example, body, engine. For example, there are the body, a cylinder block, a piston, a connecting rod, interior, exterior parts, etc. These are practical used the characteristic of a light and strong aluminum alloy efficiently. However, although an aluminum alloy is lighter than steel, the elongation is smaller than that. Therefore, in press Forming, some problems often occur. We have proposed use of Explosive Forming, in order to solve this problem. In the Explosive Forming, since a blank is formed at high speed, a strain rate effect becomes large and it can be made the elongation is larger. Then, in order to clarify this feature, we carried out experimental research and numerical analysis. In this paper, these contents will be discussed.
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High Pressure Vessel Made by Explosive Forming
ASME 2010 Pressure Vessels and Piping Conference: Volume 4, 2010Co-Authors: Hirofumi Iyama, Hideki Hamashima, Shigeru ItohAbstract:Explosive Forming is one particular Forming technique, in which, most commonly, water is used as the pressure transmission medium. In recent years, we have done the development of the method which obtains a necessary form of the metal by the control of underwater shock wave acts on the metal plate, without a metal die. On the other hand, the pressure vessel is required in various fields, but we think that the free Forming using the underwater shock wave is advantageous in the production of pressure vessel of a simple spherical, ellipse, parabola shape. In this paper, we will introduce an experiment and several numerical simulations that we carried out for this technical development.Copyright © 2010 by ASME
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Study on Explosive Forming Using Pressure Vessel and Metal Die
Volume 4: Fluid-Structure Interaction, 2007Co-Authors: Hirofumi Iyama, Shigeru ItohAbstract:Explosive Forming is one particular Forming technique, in which, most commonly, water is used as the pressure transmission medium. An Explosive is set at the top of the pressure vessel filled with water and is exploded by an electric detonator. An underwater shock wave propagates through the water medium and impinges on the metal plate causing it deformation. If a metal die is used, the metal plate deforms to a specified form. Generally, Explosive Forming has little spring back of the metal plate, because sufficient plastic deformation is obtained. There are two pressure actions to the metal plate on Explosive Forming. The first pressure pulse is from the shock loading and the second pressure pulse is caused by the expansion gas generated by the detonation of the Explosive. The secondary pressure pulse duration is longer, but the peak pressure is lower than the primary shock pressure. The intensity of the pressure pulse is based on the conditions of the pressure vessel. We have also been using the metal die for Explosive Forming. The deformation shape of the metal plate is effected by a distribution shape of shock loading. In this technique, the pressure vessel has a desired internal shape. The pressure vessel has an internal shape of a parabola. In order to understand the deformation mechanism of the metal plate, some experiments and numerical analysis were carried out.Copyright © 2007 by ASME
Hirofumi Iyama - One of the best experts on this subject based on the ideXlab platform.
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Influence of Pressure Vessel Shape on Explosive Forming
Volume 4: Fluid-Structure Interaction, 2018Co-Authors: Hirofumi Iyama, Masatoshi Nishi, Yoshikazu HigaAbstract:The Explosive Forming is a characteristic Forming method. This technique is a metal Forming using an underwater shock wave. The underwater shock wave is generated by underwater explosion of the Explosive. The metal plate is formed with involving the high strain rate on this technique. In generally, the pressure vessel is used in this method due to the effective utilization of the explosion energy. The underwater shock wave is propagated in water and reflected on inside wall of the pressure vessel. This reflected shock wave is affected on the deformation shape of a metal plate. Therefore, the inside shape of pressure vessel is often changed. In other words, the shape of pressure vessel is changed, the shock pressure distribution on the metal plate and it is possible that final deformation shape of the metal plate is changed. Some numerical simulations and experiments have been carried out to clear the influence of the inside shape of pressure vessel in the Explosive Forming. This paper is included the results and discussions on the numerical simulation and experiment used those conditions.
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Basic Research on Explosive Forming of Magnesium Alloy Plate
Materials Science Forum, 2018Co-Authors: Masatoshi Nishi, Hirofumi Iyama, Hiroko Sakaguchi, Li Qun Ruan, Masahiro FujitaAbstract:This study has investigated the plastic Forming of magnesium alloys plate. It is not easy to perform the cold-worked with the usual plastic Forming method although magnesium alloys have the advantages in terms of strength-to-weight ratio. Therefore, Explosive Forming method which is one of the plastic Forming methods with a specific Forming mechanism has been applied. At first, numerical simulations have been conducted to clarify the optimal combination conditions, and then we have verified practical effectiveness of this proposed method by using experimental study.
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Numerical Simulation of Explosive Forming Using Detonating Fuse
The International Journal of Multiphysics, 2017Co-Authors: Hirofumi Iyama, Masatoshi Nishi, Yoshikazu Higa, S ItohAbstract:The Explosive Forming is a characteristic method. An underwater shock wave is generated by underwater explosion of an Explosive. A metal plate is affected high strain rate by the shock loading and is formed along a metal die. Although this method has the advantage of mirroring the shape of the die, a free Forming was used in this paper. An expensive metal die is not necessary for this free Forming. It is possible that a metal plate is formed with simple supporting parts. However, the Forming shape is depend on the shock pressure distribution act on the metal plate. This pressure distribution is able to change by the shape of Explosive, a mass of Explosive and a shape of pressure vessel. On the other hand, we need the pressure vessel for food processing by the underwater shock wave. Therefore, we propose making the pressure vessel by this Explosive Forming. One design suggestion of pressure vessel made of stainless steel was considered. However, we cannot decide suitable conditions, the mass of the Explosive and the distance between the Explosive and the metal plate to make the pressure vessel. In order to decide these conditions, we have tried the numerical simulation on this Explosive Forming. The basic simulation method was ALE (Arbitrary Laglangian Eulerian) method including with Mie-Grumeisen EOS (equation of state), JWL EOS, Johnson-Cook constitutive equation for a material model. In this paper, the underwater pressure contours to clear the propagations of the underwater shock wave, Forming processes and deformation velocity of the metal plate is shown and it will be discussed about those results.
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Numerical simulation on manufacturing of pressure vessel for shock food processing using Explosive Forming
Volume 4: Fluid-Structure Interaction, 2016Co-Authors: Hirofumi Iyama, Masatoshi Nishi, Yoshikazu Higa, Ken Shimojima, Osamu Higa, Shigeru ItohAbstract:The Explosive Forming is a characteristic Forming method. An underwater shock wave is generated by underwater explosion of the Explosive. A metal plate is affected high strain rate by the shock loading and is formed along a metal die. Although this method has the advantage of mirroring the shape of the die, a free Forming was used in this paper. An expensive metal die is not necessary for this free Forming. It is possible that a metal plate is formed with simple supporting parts. However, the Forming shape is depend on the shock pressure distribution act on the metal plate. This pressure distribution is able to change by the shape of Explosive, a mass of Explosive and a shape of pressure vessel. On the other hand, we need the pressure vessel for food processing by the underwater shock wave. Therefore, we propose making the pressure vessel by the Explosive Forming. One design suggestion of pressure vessel made of stainless steel was considered. However, we cannot decide suitable conditions, the mass of the Explosive and the distance between the Explosive and the metal plate to make the pressure vessel. In order to decide these conditions, we have tried the numerical simulation of this Explosive Forming. The basic simulation method was ALE (Arbitrary Laglangian Eulerian) method. Mie-Grümeisen EOS (equation of state), JWL EOS, Johnson-Cook constitutive equation for a material model were applied in the numerical simulation. In this paper, the underwater pressure contours to clear the propagations of the underwater shock wave, Forming processes and deformation velocity of the metal plate is shown and it will be discussed about those results.
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A Method of Explosive Forming Process for Making a Palm and a Back of Human Hand
Materials Science Forum, 2013Co-Authors: Kazumasa Shiramoto, Hirofumi Iyama, Takumi Watanabe, Akihito Mizuno, Masahiro FujitaAbstract:t is well known as an important merit of the Explosive Forming process that the delicate figure of the die surface is precisely transferred onto the specimen of a thin metal plate, because the plate is strongly pressed against the die by the very high pressure of underwater shock wave. However, we cannot find any examples of work pieces making the best use of the merit in literatures until now. We tried to form Explosively a thin copper plate into shapes of a palm and a back of human hand, as a work piece making the best use of the merit. The palm has many small delicate lines such as fingerprints and the back has interesting figures such as loose skin at the joints of fingers and the borders of fingernails. The object of the present investigation is to make work pieces just like to a real hand. In this investigation, the following process is adopted in order to perform successfully Explosive Forming ; real hand plaster concave model convex model of Duplicone (material for dental impression) die of Ren Cast (a kind of epoxy resin) Explosive Forming. Annealed copper plates of 0.3 mm thick were used in the experiments. Since the extension limit of the plate is not so large, the plate is apt to be broken. If the plate is broken, the die is modified not to break the plate. Though the die made of epoxy resin is too hard to be modified, the plaster model can be easily modified with a cutter knife or a chisel. The modified die is obtained through model of Duplicone made by using the modified plaster model. After a few times of repeating modification, the breakage of plate was scarcely produced. On the work piece of palm, a lot of small lines including finger prints clearly appeared and the work piece of the back showed the shape just like to real human hand.
Zhang Tie-sheng - One of the best experts on this subject based on the ideXlab platform.
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Non-die Explosive Forming of spherical pressure-vessels
Journal of Materials Processing Technology, 1994Co-Authors: Zhang Rui, Zhang Tie-shengAbstract:This paper presents a newly developed method of manufacturing spherical pressure vessels based on the technology of non-die Explosive Forming. Compared with the traditional method, this technology does not need any dies and pressing equipment, so that the cost of the production process can be greatly reduced, especially for vessels of less than 100 m3 capacity.
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Explosive Forming of spherical metal vessels without dies
Journal of Materials Processing Technology, 1992Co-Authors: Zhang Tie-sheng, Li Zhensheng, Guo Changji, Tong ZhengAbstract:Abstract This paper presents a new method of manufacturing spherical vessels based on the technology of non-die Explosive Forming, that is highly energy efficient. Comparing spherical pressure vessels with other shapes of vessel, they have a higher load capacity, have less area per unit volume, have better economic benefit and have a nicer appearance: of late, they have been used increasingly.
Tong Zheng - One of the best experts on this subject based on the ideXlab platform.
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Explosive Forming of thin-wall semi-spherical parts
Materials Letters, 2000Co-Authors: He Fengman, Tong Zheng, Wang Ning, Hu ZhiyongAbstract:This paper discusses the special Forming method of thin-wall semi-spherical parts, introducing the basic fundamentals of Explosive Forming, design principles of shell-structures and related technological parameters. Investigation shows that non-die Explosive Forming is the most effective manufacturing method of such parts (G. Changji, T. Zheng, L. Zhengsheng, Non-Die Explosive Forming of Spherical Containers, Journal of Pressure Vessels, May, 1991.) having the advantages of good Forming results, high dimensional accuracy and simplicity of the process and thus may be used as a new Forming method for the spherical parts.
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Explosive Forming of spherical metal vessels without dies
Journal of Materials Processing Technology, 1992Co-Authors: Zhang Tie-sheng, Li Zhensheng, Guo Changji, Tong ZhengAbstract:Abstract This paper presents a new method of manufacturing spherical vessels based on the technology of non-die Explosive Forming, that is highly energy efficient. Comparing spherical pressure vessels with other shapes of vessel, they have a higher load capacity, have less area per unit volume, have better economic benefit and have a nicer appearance: of late, they have been used increasingly.
Teisheng Zhang - One of the best experts on this subject based on the ideXlab platform.
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optimum structure design method for non die Explosive Forming of spherical vessel technology
Journal of Materials Processing Technology, 1999Co-Authors: Rui Zhang, Masahiro Fujita, Hirifumi Iyama, Teisheng ZhangAbstract:Abstract As is already well known, the traditional working methods for manufacturing spherical shells require presses and special dies, making manufacture complex and costly. This allows less size-selection and makes the production cycle long, so that it is uneconomical to produce the spherical shell if only small amounts are produced. In order to overcome the above disadvantages and to find an easier and cheaper working method, we present the non-die Explosive Forming method. Some fundamental results have been presented previously. In this paper, we compare some structure-design methods in order to find the most practical one. In the practical working process, odd structures and even structure designs are usually used; for even structures, the four-cone and six-cone structures are commonly used, while for odd structures, the five-cone one is usually employed. However it is not clear which kind of structure is the most reasonable. Therefore, in this paper these three structures are compared. The deformation process and equivalent strain distributions were also investigated.
