Impulse-Based Manufacturing Technologies

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Guest Editor
IWU, Fraunhofer Institute for Machine Tools and Forming Technology, Reichenhainer Strasse 88, D-09126 Chemnitz, Germany
Interests: electromagnetic forming; high-speed forming process

Special Issue Information

Dear Colleagues,

In impulse-based manufacturing technologies, the energy required for forming, joining, or cutting components acts on the workpiece in a very short time and suddenly accelerates workpiece areas to very high velocities. The correspondingly high strain rates and inertia effects affect the behavior of many materials, resulting in technological benefits such as improved formability, reduced localizing and springback, extended possibilities to produce high-quality multi-material joints, and burr-free cutting. This Special Issue of JMMP will present current research findings which focus on exploiting the full potential of these processes by providing deep understanding of the technology and the material behavior and detailed knowledge about sophisticated process and equipment design. The range of considered processes covers electromagnetic forming, electrohydraulic forming, explosive forming, adiabatic cutting, forming by vaporizing foil actuators, and other impulse-based manufacturing technologies. Papers will be considered that show significant improvements for the above-mentioned processes with regard to:

  • Processes analysis;
  • Measurement technique;
  • Technology development;
  • Materials and modelling;
  • Tools and equipment; and
  • Industrial implementation.

Dr. Verena Psyk
Guest Editor

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Published Papers (13 papers)

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Editorial

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3 pages, 176 KiB  
Editorial
Impulse-Based Manufacturing Technologies
by Verena Psyk
J. Manuf. Mater. Process. 2021, 5(4), 133; https://doi.org/10.3390/jmmp5040133 - 9 Dec 2021
Viewed by 2082
Abstract
Modern manufacturing faces extensive technological and economic challenges to remain competitive under the current political and social conditions [...] Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)

Research

Jump to: Editorial

17 pages, 8459 KiB  
Article
Examples of How Increased Formability through High Strain Rates Can Be Used in Electro-Hydraulic Forming and Electromagnetic Forming Industrial Applications
by Gilles Avrillaud, Gilles Mazars, Elisa Cantergiani, Fabrice Beguet, Jean-Paul Cuq-Lelandais and Julien Deroy
J. Manuf. Mater. Process. 2021, 5(3), 96; https://doi.org/10.3390/jmmp5030096 - 1 Sep 2021
Cited by 17 | Viewed by 4164
Abstract
In order to take up some challenges in metal forming coming from the recent environmental stakes, Electromagnetic Forming and Electro-Hydraulic Forming processes have been developed at the industrial scale, using the advantages of high strain rates. Such progress has been possible in particular [...] Read more.
In order to take up some challenges in metal forming coming from the recent environmental stakes, Electromagnetic Forming and Electro-Hydraulic Forming processes have been developed at the industrial scale, using the advantages of high strain rates. Such progress has been possible in particular thanks to the emergence of strongly coupled simulation tools. In this article, some examples have been selected from some industrial applications in deep forming, postforming, embossing, and complex shapes forming. It shows how in particular, the increase in formability can bring benefits to solve customer issues in the automotive, luxury packaging, aeronautic, and particles accelerator sectors. Some simulation results are presented to explain how this highly dynamic forming occurs for each of these applications. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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35 pages, 14932 KiB  
Article
An Efficient Methodology towards Mechanical Characterization and Modelling of 18Ni300 AMed Steel in Extreme Loading and Temperature Conditions for Metal Cutting Applications
by Tiago E. F. Silva, Afonso V. L. Gregório, Abílio M. P. de Jesus and Pedro A. R. Rosa
J. Manuf. Mater. Process. 2021, 5(3), 83; https://doi.org/10.3390/jmmp5030083 - 28 Jul 2021
Cited by 5 | Viewed by 3174
Abstract
A thorough control of the machining operations is essential to ensure the successful post-processing of additively manufactured components, which can be assessed through machinability tests endowed with numerical simulation of the metal cutting process. However, to accurately depict the complex metal cutting mechanism, [...] Read more.
A thorough control of the machining operations is essential to ensure the successful post-processing of additively manufactured components, which can be assessed through machinability tests endowed with numerical simulation of the metal cutting process. However, to accurately depict the complex metal cutting mechanism, it is not only necessary to develop robust numerical models but also to properly characterize the material behavior, which can be a long-winded process, especially for state-of-stress sensitive materials. In this paper, an efficient mechanical characterization methodology has been developed through the usage of both direct and inverse calibration procedures. Apart from the typical axisymmetric specimens (such as those used in compression and tensile tests), plane strain specimens have been applied in the constitutive law calibration accounting for plastic and damage behaviors. Orthogonal cutting experiments allowed the validation of the implemented numerical model for simulation of the metal cutting processes. Moreover, the numerical simulation of an industrial machining operation (longitudinal cylindrical turning) revealed a very reasonably prediction of cutting forces and chip morphology, which is crucial for the identification of favorable cutting scenarios for difficult-to-cut materials. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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18 pages, 8472 KiB  
Article
Experimental and Numerical Investigations into Magnetic Pulse Welding of Aluminum Alloy 6016 to Hardened Steel 22MnB5
by Rico Drehmann, Christian Scheffler, Sven Winter, Verena Psyk, Verena Kräusel and Thomas Lampke
J. Manuf. Mater. Process. 2021, 5(3), 66; https://doi.org/10.3390/jmmp5030066 - 24 Jun 2021
Cited by 11 | Viewed by 3610
Abstract
By means of magnetic pulse welding (MPW), high-quality joints can be produced without some of the disadvantages of conventional welding, such as thermal softening, distortion, and other undesired temperature-induced effects. However, the range of materials that have successfully been joined by MPW is [...] Read more.
By means of magnetic pulse welding (MPW), high-quality joints can be produced without some of the disadvantages of conventional welding, such as thermal softening, distortion, and other undesired temperature-induced effects. However, the range of materials that have successfully been joined by MPW is mainly limited to comparatively soft materials such as copper or aluminum. This paper presents an extensive experimental study leading to a process window for the successful MPW of aluminum alloy 6016 (AA6016) to hardened 22MnB5 steel sheets. This window is defined by the impact velocity and impact angle of the AA6016 flyer. These parameters, which are significantly dependent on the initial gap between flyer and target, the charging energy of the pulse power generator, and the lateral position of the flyer in relation to the inductor, were determined by a macroscopic coupled multiphysics simulation in LS-DYNA. The welded samples were mechanically characterized by lap shear tests. Furthermore, the bonding zone was analyzed by optical and scanning electron microscopy including energy-dispersive X-ray spectroscopy as well as nanoindentation. It was found that the samples exhibited a wavy interface and a transition zone consisting of Al-rich intermetallic phases. Samples with comparatively thin and therefore crack-free transition zones showed a 45% higher shear tensile strength resulting in failure in the aluminum base material. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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13 pages, 7513 KiB  
Article
Influence of Material Properties on Interfacial Morphology during Magnetic Pulse Welding of Al1100 to Copper Alloys and Commercially Pure Titanium
by Shunyi Zhang and Brad L. Kinsey
J. Manuf. Mater. Process. 2021, 5(2), 64; https://doi.org/10.3390/jmmp5020064 - 18 Jun 2021
Cited by 11 | Viewed by 2741
Abstract
During magnetic pulsed welding (MPW), a wavy interface pattern can be observed. However, this depends on the specific material combination being joined. Some combinations, e.g., steel to aluminum, simply provide undulating waves, while others, e.g., titanium to copper, provide elegant vortices. These physical [...] Read more.
During magnetic pulsed welding (MPW), a wavy interface pattern can be observed. However, this depends on the specific material combination being joined. Some combinations, e.g., steel to aluminum, simply provide undulating waves, while others, e.g., titanium to copper, provide elegant vortices. These physical features can affect the strength of the joint produced, and thus a more comprehensive understanding of the material combination effects during MPW is required. To investigate the interfacial morphology and parent material properties dependency during MPW, tubular Al1100 and various copper alloy joints were fabricated. The influence of two material properties, i.e., yield strength and density, were studied, and the interface morphology features were visually investigated. Results showed that both material properties affected the interface morphology. Explicitly, decreasing yield strength (Cu101 and Cu110) led to a wavy interface, and decreasing density (Cu110 and CP-Ti) resulted in a wave interface with a larger wavelength. Numerical analyses were also conducted in LS-DYNA and validated the interface morphologies observed experimentally. These simulations show that the effect on shear stresses in the material is the cause of the interface morphology variations obtained. The results from this research provide a better fundamental understanding of MPW phenomena with respect to the effect of material properties and thus how to design an effective MPW application. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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17 pages, 1995 KiB  
Article
The Energy Balance in Aluminum–Copper High-Speed Collision Welding
by Peter Groche and Benedikt Niessen
J. Manuf. Mater. Process. 2021, 5(2), 62; https://doi.org/10.3390/jmmp5020062 - 15 Jun 2021
Cited by 1 | Viewed by 2860
Abstract
Collision welding is a joining technology that is based on the high-speed collision and the resulting plastic deformation of at least one joining partner. The ability to form a high-strength substance-to-substance bond between joining partners of dissimilar metals allows us to design a [...] Read more.
Collision welding is a joining technology that is based on the high-speed collision and the resulting plastic deformation of at least one joining partner. The ability to form a high-strength substance-to-substance bond between joining partners of dissimilar metals allows us to design a new generation of joints. However, the occurrence of process-specific phenomena during the high-speed collision, such as a so-called jet or wave formation in the interface, complicates the prediction of bond formation and the resulting bond properties. In this paper, the collision welding of aluminum and copper was investigated at the lower limits of the process. The experiments were performed on a model test rig and observed by high-speed imaging to determine the welding window, which was compared to the ones of similar material parings from former investigation. This allowed to deepen the understanding of the decisive mechanisms at the welding window boundaries. Furthermore, an optical and a scanning electron microscope with energy dispersive X-ray analysis were used to analyze the weld interface. The results showed the important and to date neglected role of the jet and/or the cloud of particles to extract energy from the collision zone, allowing bond formation without melting and intermetallic phases. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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20 pages, 66898 KiB  
Article
Electrohydraulic Forming of Low Volume and Prototype Parts: Process Design and Practical Examples
by Alexander V. Mamutov, Sergey F. Golovashchenko, Nicolas M. Bessonov and Viacheslav S. Mamutov
J. Manuf. Mater. Process. 2021, 5(2), 47; https://doi.org/10.3390/jmmp5020047 - 13 May 2021
Cited by 6 | Viewed by 4176
Abstract
Electro-Hydraulic Forming (EHF) is a high rate sheet metal forming process based on the electrical discharge of high voltage capacitors in a water-filled chamber. During the discharge, the pulsed pressure wave propagates from the electrodes and forms a sheet metal blank into a [...] Read more.
Electro-Hydraulic Forming (EHF) is a high rate sheet metal forming process based on the electrical discharge of high voltage capacitors in a water-filled chamber. During the discharge, the pulsed pressure wave propagates from the electrodes and forms a sheet metal blank into a die. The performed literature review shows that this technology is suitable for forming parts of a broad range of dimensions and complex shapes. One of the barriers for broader implementation of this technology is the complexity of a full-scale simulation of EHF which includes the simulation of an expanding plasma channel, the propagation of waves in a fluid filled chamber, and the high-rate forming of a blank in contact with a rigid die. The objective of the presented paper is to establish methods of designing the EHF processes using simplified methods. The paper describes a numerical approach on how to define the shape of preforming pockets. The concept includes imposing principal strains from the formed blank into the initial mesh of the flat blank. The principal strains are applied with the opposite sign creating compression in the flat blank. The corresponding principal stresses in the blank are calculated based upon Hooke’s law. The blank is then virtually placed between two rigid plates. One of the plates has windows into which the material is getting bulged driven by the in-plane compressive stresses. The prediction of the shape of the bulged sheet provides the information on the shape of the preforming pockets. It is experimentally demonstrated that using these approaches, EHF forming is feasible for forming of a fragment of a decklid panel and a deep panel with complex curvature. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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20 pages, 8181 KiB  
Article
Analysis of Proximity Consequences of Coil Windings in Electromagnetic Forming
by Siddhant Prakash Goyal, Mohammadjavad Lashkari, Awab Elsayed, Marlon Hahn and A. Erman Tekkaya
J. Manuf. Mater. Process. 2021, 5(2), 45; https://doi.org/10.3390/jmmp5020045 - 8 May 2021
Cited by 3 | Viewed by 3117
Abstract
Multiturn coils are required for manufacturing sheet metal parts with varying depths and special geometrical features using electromagnetic forming (EMF). Due to close coil turns, the physical phenomena of the proximity effect and Lorentz forces between the parallel coil windings are observed. This [...] Read more.
Multiturn coils are required for manufacturing sheet metal parts with varying depths and special geometrical features using electromagnetic forming (EMF). Due to close coil turns, the physical phenomena of the proximity effect and Lorentz forces between the parallel coil windings are observed. This work attempts to investigate the mechanical consequences of these phenomena using numerical and experimental methods. A numerical model was developed in LS-DYNA. It was validated using experimental post-mortem strain and laser-based velocity measurements after and during the experiments, respectively. It was observed that the proximity effect in the parallel conductors led to current density localization at the closest or furthest ends of the conductor cross-section and high local curvature of the formed sheet. Further analysis of the forces between two coil windings explained the departure from the “inverse-distance” rule observed in the literature. Finally, some measures to prevent or reduce undesired coil deformation are provided. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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14 pages, 7741 KiB  
Article
Adiabatic Blanking: Influence of Clearance, Impact Energy, and Velocity on the Blanked Surface
by Sven Winter, Matthias Nestler, Elmar Galiev, Felix Hartmann, Verena Psyk, Verena Kräusel and Martin Dix
J. Manuf. Mater. Process. 2021, 5(2), 35; https://doi.org/10.3390/jmmp5020035 - 13 Apr 2021
Cited by 16 | Viewed by 3769
Abstract
In contrast to other cutting processes, adiabatic blanking typically features high blanking velocities (>3 m/s), which can lead to the formation of adiabatic shear bands in the blanking surface. The produced surfaces have excellent properties, such as high hardness, low roll-over, and low [...] Read more.
In contrast to other cutting processes, adiabatic blanking typically features high blanking velocities (>3 m/s), which can lead to the formation of adiabatic shear bands in the blanking surface. The produced surfaces have excellent properties, such as high hardness, low roll-over, and low roughness. However, details about the qualitative and quantitative influence of significant process parameters on the quality of the blanked surface are still lacking. In the presented study, a variable tool is used for a systematic investigation of different process parameters and their influences on the blanked surface of a hardened 22MnB5 steel. Different relative clearances (1.67% to 16.67%), velocities (7 to 12.5 m/s), and impact energies (250 J to 1000 J) were studied in detail. It is demonstrated that a relative clearance of ≤6.67% and an impact velocity of ≥7 m/s lead to adiabatic shear band formation, regardless of the impact energy. Further, an initiated shear band results in the formation of an S-shaped surface. Unexpectedly, a low impact energy results in the highest geometric accuracy. The influence of the clearance, the velocity, and the impact energy on the evolution of adiabatic shear band formation is shown for the first time. The gained knowledge can enable a functionalization of the blanked surfaces in the future. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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14 pages, 7072 KiB  
Article
Numerical and Experimental Investigation of the Impact of the Electromagnetic Properties of the Die Materials in Electromagnetic Forming of Thin Sheet Metal
by Björn Beckschwarte, Lasse Langstädtler, Christian Schenck, Marius Herrmann and Bernd Kuhfuss
J. Manuf. Mater. Process. 2021, 5(1), 18; https://doi.org/10.3390/jmmp5010018 - 12 Feb 2021
Cited by 10 | Viewed by 2545
Abstract
In electromagnetic forming of thin sheet metal, the die is located within the effective range of the electromagnetic wave. Correspondingly, a current is induced not only in the sheet metal, but also in the die. Like the current in the workpiece, also the [...] Read more.
In electromagnetic forming of thin sheet metal, the die is located within the effective range of the electromagnetic wave. Correspondingly, a current is induced not only in the sheet metal, but also in the die. Like the current in the workpiece, also the current in the die interacts with the electromagnetic wave, resulting in Lorentz forces and changes of the electromagnetic field. With the aim to study the influence of different electromagnetic die properties in terms of specific electric resistance and relative magnetic permeability, electromagnetic simulations were carried out. A change in the resulting forming forces in the sheet metals was determined. To confirm the simulation results, electromagnetic forming and embossing tests were carried out with the corresponding die materials. The results from simulation and experiment were in good agreement. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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19 pages, 14161 KiB  
Article
Probing Magnetic Pulse Welding of Thin-Walled Tubes
by Koen Faes, Rishabh Shotri and Amitava De
J. Manuf. Mater. Process. 2020, 4(4), 118; https://doi.org/10.3390/jmmp4040118 - 11 Dec 2020
Cited by 14 | Viewed by 3921
Abstract
Magnetic pulse welding is a solid-state joining technology, based on the use of electromagnetic forces to deform and to weld workpieces. Since no external heat sources are used during the magnetic pulse welding process, it offers important advantages for the joining of dissimilar [...] Read more.
Magnetic pulse welding is a solid-state joining technology, based on the use of electromagnetic forces to deform and to weld workpieces. Since no external heat sources are used during the magnetic pulse welding process, it offers important advantages for the joining of dissimilar material combinations. Although magnetic pulse welding has emerged as a novel technique to join metallic tubes, the dimensional consistency of the joint assembly due to the strong impact of the flyer tube onto the target tube and the resulting plastic deformation is a major concern. Often, an internal support inside the target tube is considered as a solution to improve the stiffness of the joint assembly. A detailed investigation of magnetic pulse welding of Cu-DHP flyer tubes and 11SMnPb30 steel target tubes is performed, with and without an internal support inside the target tubes, and using a range of experimental conditions. The influence of the key process conditions on the evolution of the joint between the tubes with progress in time has been determined using experimental investigations and numerical modelling. As the process is extremely fast, real-time monitoring of the process conditions and evolution of important responses such as impact velocity and angle, and collision velocity, which determine the formation of a metallic bond, is impossible. Therefore, an integrated approach using a computational model using a finite-element method is developed to predict the progress of the impact of the flyer onto the target, the resulting flyer impact velocity and angle, the collision velocity between the flyer and the target, and the evolution of the welded joint, which are usually impossible to measure using experimental observations. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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12 pages, 4428 KiB  
Article
A Rapid Throughput System for Shock and Impact Characterization: Design and Examples in Compaction, Spallation, and Impact Welding
by K. Sajun Prasad, Yu Mao, Anupam Vivek, Stephen R. Niezgoda and Glenn S. Daehn
J. Manuf. Mater. Process. 2020, 4(4), 116; https://doi.org/10.3390/jmmp4040116 - 10 Dec 2020
Cited by 6 | Viewed by 3585
Abstract
Many important physical phenomena are governed by intense mechanical shock and impulse. These can be used in material processing and manufacturing. Examples include the compaction or shearing of materials in ballistic, meteor, or other impacts, spallation in armor and impact to induce phase [...] Read more.
Many important physical phenomena are governed by intense mechanical shock and impulse. These can be used in material processing and manufacturing. Examples include the compaction or shearing of materials in ballistic, meteor, or other impacts, spallation in armor and impact to induce phase and residual stress changes. The traditional methods for measuring very high strain rate behavior usually include gas-guns that accelerate flyers up to km/s speeds over a distance of meters. The throughput of such experiments is usually limited to a few experiments per day and the equipment is usually large, requiring specialized laboratories. Here, a much more compact method based on the Vaporizing Foil Actuator (VFA) is used that can accelerate flyers to over 1 km/s over a few mm of travel is proposed for high throughput testing in a compact system. A system with this primary driver coupled with Photonic Doppler Velocimetry (PDV) is demonstrated to give insightful data in powder compaction allowing measurements of shock speed, spall testing giving fast and reasonable estimates of spall strength, and impact welding providing interface microstructure as a function of impact angle and speed. The essential features of the system are outlined, and it is noted that this approach can be extended to other dynamic tests as well. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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21 pages, 10699 KiB  
Article
Magnetic Pulse Welding and Spot Welding with Improved Coil Efficiency—Application for Dissimilar Welding of Automotive Metal Alloys
by Chady Khalil, Surendar Marya and Guillaume Racineux
J. Manuf. Mater. Process. 2020, 4(3), 69; https://doi.org/10.3390/jmmp4030069 - 8 Jul 2020
Cited by 24 | Viewed by 5790
Abstract
Lightweight structures in the automotive and transportation industry are increasingly researched. Multiple materials with tailored properties are integrated into structures via a large spectrum of joining techniques. Welding is a viable solution in mass scale production in an automotive sector still dominated by [...] Read more.
Lightweight structures in the automotive and transportation industry are increasingly researched. Multiple materials with tailored properties are integrated into structures via a large spectrum of joining techniques. Welding is a viable solution in mass scale production in an automotive sector still dominated by steels, although hybrid structures involving other materials like aluminum are becoming increasingly important. The welding of dissimilar metals is difficult if not impossible, due to their differential thermo mechanical properties along with the formation of intermetallic compounds, particularly when fusion welding is envisioned. Solid-state welding, as with magnetic pulse welding, is of particular interest due to its short processing cycles. However, electromagnetic pulse welding is constrained by the selection of processing parameters, particularly the coil design and its life cycle. This paper investigates two inductor designs, a linear (I) and O shape, for the joining of sheet metals involving aluminum and steels. The O shape inductor is found to be more efficient both with magnetic pulse (MPW) and magnetic pulse spot welding (MPSW) and offers a better life cycle. Both simulation and experimental mechanical tests are presented to support the effect of inductor design on the process performance. Full article
(This article belongs to the Special Issue Impulse-Based Manufacturing Technologies)
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