Investigation of Weld Seam Structures of Tailor Welded Blanks for Hot Stamping

Abstract:

Increasing safety requirements for hot stamped structural car body parts are demanding sufficient mechanical properties of integrated welding seams. Especially conventional tailor welded AlSi-coated 22MnB5 sheets are only fulfilling these requirements when ablated before laser welding and thermo-mechanically treated in a correct way. This paper shows a method that evaluates the hot stamping process of tailor welded blanks by press hardening different sheet thicknesses and thickness combinations in a testing tool. Furthermore, appropriate testing methods for the evaluation of mechanical properties of the welding seam are introduced. The results are ultimately compared with a special developed FEM analysis to predict failure cases in future.

• Periodical: Key Engineering Materials (Volume 639)
• Pages: 235-242
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.639.235
• Online since: March 2015
• Authors: Ralf Kolleck*, Robert Vollmer, Christian Both, Arndt Breuer
• Keywords: Heat Transfer, Hot Stamping, Sheet Metal, Tailor Welded Blank

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