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:
The constant demand of increasing performances and safety in vehicle industry has ledsignificant innovations in the materials used in sheet metal forming processes. In particular, multiphasesteels and lightweight alloys have known higher and higher importance, thanks to thedevelopment of new stamping processes at elevated temperatures, which guarantee, at the sametime, better formability, lower springback and more accurate micro-structural control in the formedsheets. With respect to these aspects, the correct design and optimization of the new processescannot prescind of the mechanical characterization of materials in biaxial stress conditions,especially when it strongly varies according to the stress and temperature. In this paper, a novelexperimental set-up is presented for determining the in-plane yield locus of sheet metals at elevatedtemperatures. A cruciform specimen, whose geometry was optimized by numerical simulation, isused for the study of the yield locus in the range of biaxial tensile stresses. The test machine conceptis based on punch-wedge mechanism, which uses the vertical movement of the press for thedeformation of the specimen along two perpendicular axes. In the first part of the paper, theoptimization of the cruciform specimen by thermo-mechanical FE analyses is outlined. Details onthe experimental set-up are then given with the description of the apparatus, the measurement ofplastic strains and the heating system for tests at elevated temperatures
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/54/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.344.97.pdf
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