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Title: Numerical Method to Analyze Local Stiffness of the Workpiece to avoid Rebound During Electromagnetic Sheet Metal Forming

Abstract

Electromagnetic sheet metal forming is a high speed forming process using pulsed magnetic fields to form metals with high electrical conductivity such as aluminum. Thereby, workpiece velocities of more than 300 m/s are achievable, which can cause difficulties when forming into a die: the kinetic energy, which is related to the workpiece velocity, must dissipate in a short time slot when the workpiece hits the die; otherwise undesired effects, for example rebound, can occur. One possibility to handle this shortcoming is to locally increase the stiffness of the workpiece. In order to be able to estimate the local stiffness a method is presented which is based on a modal analysis by means of the Finite-Element-Method. For this reason, it is necessary to fractionize the considered geometries into a part-dependent number of segments. These are subsequently analyzed separately to determine regions of low geometrical stiffness. Combined with the process knowledge concerning the velocity distribution within the workpiece over the time, a prediction of the feasibility of the forming process and a target-oriented design of the workpiece geometry will be possible. Numerical results are compared with experimental investigations.

Authors:
; ; ;  [1]
  1. Institute of Forming Technology and Lightweight Construction, University of Dortmund, Baroper Str. 301, 44227 Dortmund (Germany)
Publication Date:
OSTI Identifier:
21057006
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729507; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; ALUMINIUM ALLOYS; DESIGN; DISTRIBUTION; ELECTRIC CONDUCTIVITY; ELECTRODEPOSITION; FINITE ELEMENT METHOD; FLEXIBILITY; KINETIC ENERGY; MAGNETIC FIELDS; MAGNETIC FORMING; SHEETS

Citation Formats

Risch, Desiree, Brosius, Alexander, Psyk, Verena, and Kleiner, Matthias. Numerical Method to Analyze Local Stiffness of the Workpiece to avoid Rebound During Electromagnetic Sheet Metal Forming. United States: N. p., 2007. Web. doi:10.1063/1.2729507.
Risch, Desiree, Brosius, Alexander, Psyk, Verena, & Kleiner, Matthias. Numerical Method to Analyze Local Stiffness of the Workpiece to avoid Rebound During Electromagnetic Sheet Metal Forming. United States. doi:10.1063/1.2729507.
Risch, Desiree, Brosius, Alexander, Psyk, Verena, and Kleiner, Matthias. Sat . "Numerical Method to Analyze Local Stiffness of the Workpiece to avoid Rebound During Electromagnetic Sheet Metal Forming". United States. doi:10.1063/1.2729507.
@article{osti_21057006,
title = {Numerical Method to Analyze Local Stiffness of the Workpiece to avoid Rebound During Electromagnetic Sheet Metal Forming},
author = {Risch, Desiree and Brosius, Alexander and Psyk, Verena and Kleiner, Matthias},
abstractNote = {Electromagnetic sheet metal forming is a high speed forming process using pulsed magnetic fields to form metals with high electrical conductivity such as aluminum. Thereby, workpiece velocities of more than 300 m/s are achievable, which can cause difficulties when forming into a die: the kinetic energy, which is related to the workpiece velocity, must dissipate in a short time slot when the workpiece hits the die; otherwise undesired effects, for example rebound, can occur. One possibility to handle this shortcoming is to locally increase the stiffness of the workpiece. In order to be able to estimate the local stiffness a method is presented which is based on a modal analysis by means of the Finite-Element-Method. For this reason, it is necessary to fractionize the considered geometries into a part-dependent number of segments. These are subsequently analyzed separately to determine regions of low geometrical stiffness. Combined with the process knowledge concerning the velocity distribution within the workpiece over the time, a prediction of the feasibility of the forming process and a target-oriented design of the workpiece geometry will be possible. Numerical results are compared with experimental investigations.},
doi = {10.1063/1.2729507},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
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