3^rd Generation AHSS : Mechanistic Responses Enabling Cold Deformation during Stamping

Abstract:

Due to increasingly stringent regulations governing fuel economy and emissions, new technological developments towards automobile efficiency are in play including lightweighting by reducing weight of the structural components. The historical development of steel grades for autos has resulted in strength increases, including in recent advanced high strength steels (AHSS), but it has come with commensurate decreases in ductility and formability. NanoSteel 3^rd Generation AHSS overcomes the trade-off in ductility due to novel structural changes during cold deformation through a complex Nanophase Refinement and Strengthening (NR&S) mechanism leading to material strengthening. During stamping, the ability of a steel blank to be formed into complex parts is paramount and it has to retain sufficient ductility for energy absorption during a subsequent crash event. In this paper, the specific characteristics of the NR&S mechanism in two NanoSteel grades will be detailed including structure and property changes during stamping analyzed by utilizing destructive and non-destructive approaches to predict localized yield strength changes in the final stampings.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 542-551
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.542
• Online since: December 2018
• Authors: Daniel James Branagan*, Craig S. Parsons, Tad V. Machrowicz, Andy E. Frerichs, Brian E. Meacham, Sheng Cheng, Alla V. Sergueeva
• Keywords: AHSS, AutoSteel, Cold Formability, Ductility, Metal Stamping, Strength

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