ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Hemming is the last or one of the latest stage operations for the stamped parts. For thisreason it has a critical importance on the performance and perceived quality of assembled vehicles.It is used to attach two sheet metal parts together or to improve appearance creating a smooth edgerather than a razor edge with burrs.However, designing the hemmed union is not always easy and is deeply influenced by themechanical properties of the material of the bended part. Main problems for the automotive industryarise when bending aluminum alloys.Aluminum sheet is more difficult to hem due to its susceptibility to strain localization during thehemming process. This phenomenon produces cracking on the hemmed edge [1].In order to avoid this problem and due to the limitations of conventional flanging and hemmingtechnologies, the flange radii must be increased and a rope hem used (instead of the flat hem usedwith steels) when working with aluminum alloys. These changes on the design of the hem uniongive as a result a lower quality final product [2].Dies and tools used for the hemming process are designed based on experience and on lengthy andcostly die tryouts.Continuing with the development of new applications for the Electromagnetic Forming (EMF)technology, LABEIN-Tecnalia and Professor Glenn Daehn’s group from The Ohio State Universitycarried out some first straight flat hemming experiments using the AA 6016 T4 aluminum alloy.The results obtained from these first trials are presented in this paper giving a first sight of thepossibilities, advantages and disadvantages of using the Electromagnetic Forming technology forthe hemming of aluminum sheet panels.Using a non-clouped FEM simulation method, the experimental results are compared to the onesobtained with the simulations.The future working line in developing this new application for the Electromagnetic Formingtechnology will be based on the results obtained by this study
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/54/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.344.365.pdf
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