ThyssenKrupp Steel Europe AG (Dortmund, Germany):

Blumenau M., Head of Continuous Annealing, Cold Rolling Shop No. 3, e-mail: marc.blumenau@thyssenkrupp.com

ThyssenKrupp Steel Europe AG (Duisburg, Germany):
Bäumer A., Head of the Project for Development of Multi-Phase Steels — Technology and Innovation

The aim of this paper was to present challenges and chances in the continuous annealing process of AHSS. It was shown how the line operators of the CAL of ThyssenKrupp Steel Europe in Dortmund meet these challenges. Additionally, specific chances given by the continuous annealing process to produce AHSS were illustrated. The following 4 innovations have been described. Firstly, the problems of processing of AHSS steels are connected with high strength and high content of alloying materials in these steels. Secondly, modernization and optimization of the technology and control remedies are required to solve these problems. Thirdly, strip surface quality and operating flexibility are the main advantages of the CAL line in comparison with hot-dip galvanizing of AHSS steels. Fourthly, the a.m. Advantages allow to use such steels in automotive industry providing more light weight of car body owing to improvement of steel quality. Summarizing, the production of AHSS in an industrial CAL raises demanding tasks and drives the line operator to a continuous process development in order to meet the continuous progress in material development. If these tasks can be fulfilled, AHSS for sophisticated applications can be offered to the market. Regarding current and future trends in material development towards increasing amounts of alloying elements and innovative heat-treatments (e. g. quench and partitioning process) continuous annealing will keep an important position in the production path of high-quality steel strips.

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