Influence of Tooling Material and Temperature on the Final Properties of Tailor Tempered Boron Steels

Abstract:

Hot forming processes are becoming a successful solution when complex geometrical components with high mechanical properties are desired. In fact, automotive structural components with tensile strengths higher than 1500MPa are being nowadays industrially produced. The technology is based on the forming and quenching of the sheet inside the forming tool using boron steels. Aiming at boosting the advantages of this technology, car manufacturers have started to demand structural components with different mechanical behavior areas in order to improve the impact response of the auto-motive passenger compartment: the so called tailor tempered components. The basic idea is to obtain final parts with different properties like it has been successfully done using tailored welded blanks. Although different solutions exist, one of the most common strategy is to use partially heated tooling, which influences the cooling of the sheet and consequently the local properties. At the present work, a special tooling with independent heated and cooled areas has been developed in order to evaluate the final properties achievable in the tailored tempering process. Furthermore, high and low conductivity alloys have been used to find the process limits. Hardness values, Ultimate Tensile Stresses and microstructures are shown for different steels, tool temperatures and contact pressures

• Periodical: Key Engineering Materials (Volumes 611-612)
• Pages: 1102-1109
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.611-612.1102
• Online since: May 2014
• Authors: Lander Galdos*, Eneko Sáenz de Argandoña, Nuria Herrero, Aitor Sukia, Rafa Ortubay, Xabier Agirretxe, Jatsu Intxaurbe
• Keywords: Boron Steels, Hot Stamping, Tailor Tempering

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