Examples of How Increased Formability through High Strain Rates Can Be Used in Electro-Hydraulic Forming and Electromagnetic Forming Industrial Applications

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.

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Transient Simulation of Electromagnetic Forming of Aluminium Tubes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.6-8.639 ◽

2005 ◽

Vol 6-8 ◽

pp. 639-648 ◽

Cited By ~ 16

Author(s):

C. Karch ◽

Karl Roll

Keyword(s):

Eddy Currents ◽

High Strain ◽

Electromagnetic Forming ◽

Numerical Representation ◽

Strain Rates ◽

High Strain Rates ◽

Forming Process ◽

Transient Electromagnetic ◽

Deformation Properties ◽

Stress And Deformation

The recent push to use more aluminium in automobiles has stimulated interest in understanding electromagnetic forming (EMF), which uses induced electromagnetic fields to generate high strain rates during the forming process. The high strain rates increase the formability of aluminum materials and might reduce elastic spring-back and wrinkling of the workpiece. Primary emphasis is placed on including of all relevant physical phenomena, which govern the process, as well as their numerical representation by means of simplified electrical equivalent circuits for the EMF machine and fully coupled field approach of the transient electromagnetic and mechanical phenomena. Moreover, the thermal effects due to Joule heating by eddy currents and plastic work are considered. The numerical model predicts the electromagnetic field, temperature, stress, and deformation properties that occur during the forming process. The numerical results of the tube deformation are compared with available experimental data.

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Sheet Metal Forming Research in Japan

Journal of Engineering for Industry ◽

10.1115/1.3670880 ◽

1966 ◽

Vol 88 (1) ◽

pp. 101-110 ◽

Cited By ~ 2

Author(s):

S. Fukui ◽

K. Yoshida ◽

S. Kobayashi

Keyword(s):

Sheet Metal ◽

Sheet Metal Forming ◽

Metal Forming ◽

High Strain ◽

High Energy ◽

Stress And Strain ◽

Strain Rates ◽

High Strain Rates ◽

Press Forming ◽

Flange Forming

Research activities and their results on sheet metal forming in Japan are introduced with emphasis on the mechanics of sheet metal press-forming. Based on the governing deformation mechanisms and the characteristics of forming limits, sheet metal press-forming processes are classified into deep drawing, bulging, stretch flange forming, and bending. According to this classification, formability and its testing can systematically be evaluated with the aid of the analysis of process mechanics. For the stress and strain analyses, the method of calculation is well established and the use of a computer reveals the detail stress and strain distributions in the process. A basic problem in high energy rate processes is the mechanical behavior of materials at high strain rates, and the deformation of sheet metals in high-speed tension test is discussed. There are many problems still left for the future. A few of these are the conditions of instability and fracture, the effect of anisotropy, the analysis considering the stress and strain variations in the thickness direction, formabilities, the properties of materials at high strain rates, tool wear, and tool deformations.

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