Hot Stamped Aluminium for Crash-Resistant Automobile Safety Cage Applications

Abstract:

Hot stamping, also known as press hardening in the context of sheet steel, has steadily gained relevance in the automotive industry, starting off as a specialist application and turning into a staple technique in the production of safety cage products in little more than a decade. However, despite the weight reduction offered by martensitic steels, further improvement could be obtained by substituting these components by high-performance aluminium. In this regard, the very same process of hot stamping could be employed to attain the required combination of shape complexity and mechanical properties at a reasonable cost for mass-market application, if the limitations imposed by cycle time and process window could be overcome. In this work, the feasibility of hot stamping of 6000-series aluminium alloy sheet is studied, first in dilatometry experiments and later in semi-industrial conditions in a pilot facility. A cycle time shortening strategy is employed, and compared to the conventional thermal cycle in terms of implementation and obtained results. In addition to basic characterization, aluminium thus processed is studied in terms of fracture toughness, in order to obtain data relevant to crashworthiness that can be readily compared with alternative materials.

• Periodical: Materials Science Forum (Volume 1016)
• Pages: 445-452
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1016.445
• Online since: January 2021
• Authors: Jaume Pujante, David Frómeta*, Eduard Garcia-Llamas, Maria Gimenez, Daniel Casellas
• Keywords: Aluminium, Automotive, Crashworthiness, Essential Work of Fracture, Hot Stamping

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