Abstract
The reinforcement of metastable austenitic steels during deep drawing to utilize the α’-martensitic phase transformation in combination with the work-hardening effect is one concept of lightweight construction. One aim concerning this contribution is the material characterization of those local strain-induced reinforcements in sheet metal. After a short introduction in the field of enhancing stiffness during forming processes, crash tests and Nakajima tests are analyzed regarding their applicability for the modified material. The successful determination of the reaction of flexure and the energy absorption was realized by crash tests, including the comparison of reinforced and original material. To adapt well established methods for the material characterization for this special case, new approaches for this challenge were developed to evaluate the material behavior for different states of stress according to Nakajima tests. Thus, the developed Forming Curves (FC) enable the determination of varied failure areas and the material behavior of reinforced and original steel including bulge height. The FCs allow a comparison of different reinforced steel grades considering the deformation of reinforcements during the Nakajima test.
References
B.-A. Behrens, C. Sunderkötter, S. Hübner, J. Knigge, K. Weilandt, K. Voges-Schwieger. Local Strain Hardening of Sheet and Solid Forming Components during Formation of Martensite in Metastable Austenitic Steels In Advanced Materials Research Vol. 22, pages 5-15, 2007.
NGV project management. Edelstahlhersteller zeigen Zukunft des Autos. Konstruktion 11/12, Springer VDI-Verlag, page IW 12, 2007.
E. Doege, C. Frank, H. Schulz-Marner, T. Hallfeldt. Gezielte lokale Festigkeitssteigerung in Feinblechen mittels Durchwalken. Bänder Bleche Rohre, pages 26-28, 1997.
W.Abramowicz, N. Jones. Dynamic Progressive Buckling of Circular and Square Tubes. International Journal of Impact Engineering. Vol. 4. No. 4, pages 243-270, 1986.
B.-A Behrens, H. Palkowski. Bestimmung von Kennwerten zur Beschreibung der Umformeigenschaften neuer und gefügter Feinblechhalbzeuge für den Streckzieh- und Tiefziehprozess durch vergleichende Untersuchungen. Annual report of the Collaborative Research Centre 362, Sheet Metal Processing”, pages A2-1 – A2-57, 2006.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Voges-Schwieger, K., Hübner, S. & Behrens, BA. Material characterization of local strain-induced α’-martensitic reinforcements. Int J Mater Form 2 (Suppl 1), 1 (2009). https://doi.org/10.1007/s12289-009-0452-6
Published:
DOI: https://doi.org/10.1007/s12289-009-0452-6