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The industry scale production of heavy steel plates is performed in plate mills using reversing mill stands and roll schedules with 30 or more passes. Ideal pass scheduling is dependent on a precise prediction of the roll force in each pass. To obtain these forces process models based on the slab theory together with semi-empirical material models are most frequently used. The material parameters necessary to calibrate the models for a specific steel grade are conventionally generated on a lab scale via time-consuming and expensive compression tests. This paper will introduce a concept that allows obtaining the material model parameters directly from the rolling process on an industrial scale by an inverse modeling technique. In this context, the parameters of the material model are adjusted according to the current offset between measured and calculated roll forces. The adjustment is enabled by a non-linear optimization that aims for a minimum deviation between measured and calculated roll forces for each pass. Several results gathered in an optimization run with industrial data of about 2650 produced plates are presented. The concurrence between measurement and prediction using the optimal parameters is in detail shown for three different schedules. In summary, inverse modeling seems to allow utilizing data of past rolling processes to determine material model parameters with high accuracy.

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The magnetic properties of non-oriented electrical steel, widely used in electric machines, are closely related to the grain size and texture of the material. How to control the evolution of grain size and texture through processing in order to improve the magnetic properties is the research focus of this article. Therefore, the complete process chain of a non-oriented electrical steel with 3.2 wt.-% Si was studied with regard to hot rolling, cold rolling, and final annealing on laboratory scale. Through a comprehensive analysis of the process chain, the influence of important process parameters on the grain size and texture evolution as well as the magnetic properties was determined. It was found that furnace cooling after the last hot rolling pass led to a fully recrystallized grain structure with the favorable ND-rotated-cube component, and a large portion of this component was retained in the thin strip after cold rolling, resulting in a texture with a low γ-fiber and a high ND-cube component after final annealing at moderate to high temperatures. These promising results on a laboratory scale can be regarded as an effective way to control the processing on an industrial scale, to finally tailor the magnetic properties of non-oriented electrical steel according to their final application.