Markus Grillenberger, Martin Schagerl,
"Yield Stress Analysis in Dynamic Compression Tests for Sheet Metal, Using Experimental Data"
: Proceedings of 17th International Conference on Experimental Mechanics, Rhodes, Greece, 7-2016

Original Titel:

Yield Stress Analysis in Dynamic Compression Tests for Sheet Metal, Using Experimental Data

Sprache des Titels:

Englisch

Original Buchtitel:

Proceedings of 17th International Conference on Experimental Mechanics, Rhodes, Greece

Original Kurzfassung:

The development of advanced empiric constitutive laws for accurate prediction of yield be-havior and their implementation into finite element method solvers require the identification of material parameters. Therefore a matter of interest is the knowledge of the material be-havior up to large deformation at different strain rates determined by experimental data. The deformation and deformation rates in common test methods (tension test, plane strain com-pression test) are not sufficient to get full information on the material behavior especially at yielding. Here a compression test seems to be appropriate. However, the directly measured yield data is not accurate enough for defining exact material models for use in numerical analyses. This is caused by influences such as friction which leads to boundary constrains and thus to a multiaxial stress state at increasing deformation. This article proposes a meth-od to compute the actual stress in the dynamic compression test taking into account the in-creasing contact surface and the "ballooning" effect caused by friction. The method is based on numerical analysis and experimental data. The experimental data are gained from dynam-ic compression tests at different strain rate levels using different specimen geometries.

Sprache der Kurzfassung:

Englisch

Englischer Titel:

YIELD STRESS ANALYSIS IN DYNAMIC COMPRESSION TESTS FOR SHEET METAL, USING EXPERIMENTAL DATA

Englische Kurzfassung:

The development of advanced empiric constitutive laws for accurate prediction of yield be-havior and their implementation into finite element method solvers require the identification of material parameters. Therefore a matter of interest is the knowledge of the material be-havior up to large deformation at different strain rates determined by experimental data. The deformation and deformation rates in common test methods (tension test, plane strain com-pression test) are not sufficient to get full information on the material behavior especially at yielding. Here a compression test seems to be appropriate. However, the directly measured yield data is not accurate enough for defining exact material models for use in numerical analyses. This is caused by influences such as friction which leads to boundary constrains and thus to a multiaxial stress state at increasing deformation. This article proposes a meth-od to compute the actual stress in the dynamic compression test taking into account the in-creasing contact surface and the "ballooning" effect caused by friction. The method is based on numerical analysis and experimental data. The experimental data are gained from dynam-ic compression tests at different strain rate levels using different specimen geometries.