Influence of the Hot Rolling Process on the Mechanical Behaviour of Martensitic Steel

Abstract:

The increased demand for advanced high-strength steels (AHSS) is driven mainly by the need of the automotive industry to reduce weight and to improve safety. Beside good ductility and high strength, those steels have a high bake hardening (BH) effect, giving additional contribution to the strength of structural parts, subjected to the paint baking process. In this paper results are presented gained from hot rolled martenstitic steels. For the simulation of changing conditions within the final hot rolling process the specimens were hot deformed using different schedules changing reductions and temperatures been selected according to the non-recrystallization temperature By controlling the deformation temperature and the amount of strain below non-recrystallization during the thermomechanically controlled process it was possible to refine the martensitic steel structure, resulting in an improved strength and BH behaviour. A wide spectrum of mechanical properties could be obtained. The best strength and BH levels were recorded where the deformation was applied below T_nRX at the highest amount of strain.

• Periodical: Advanced Materials Research (Volume 409)
• Pages: 653-659
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.409.653
• Online since: November 2011
• Authors: Mehdi Asadi, Heinz Palkowski
• Keywords: Bake Hardening, Hot Deformation, Martensitic Steel

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