This paper presents research activities regarding the systematic error of the pressure measurement film when measuring the area of the wheel–rail contact. In particular, an explanation for the different error values shown by the different film types was sought. A finite element model was created based on the assumption that not only the film, but also the microcapsules on top of it alter the results. The performance of the existing film models was enhanced by defining microcapsules with element failure and deletion behaviors. The new model was capable of reproducing the trend shown by the systematic error in the experiments. The simulation results confirmed that the measurement error of a certain film type is not only caused by the film itself, but also depends on the failure pressure and especially the diameter of the capsules.

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Heavy plates are products of global economic relevance. Due to the high requirements for this semifinished product, the trend in heavy plate processing is toward providing ever higher quality steels that, for instance, combine a predefined yield point, good weldability, and, at the same time, predefined toughness properties. Unprecedented quality requirements in steel processing can only be met if technologically relevant parameters, such as temperature, are guaranteed to be kept within a narrow tolerance range during the hotrolling process, one of the most decisive steps within the production chain for heavy plates. Within the heavy plate hot-rolling process, often performed in a reversing four-high mill stand consisting of a pair of work rolls and a pair of backup rolls, various production steps like rolling passes, descaling sequences, and cooling periods, determine the plate's temperature evolution. [1] In parallel, temperature evolution affects the microstructure and, thus, associated physical properties of the final product, such as hardness and toughness. [2] It is, therefore, of utmost importance to consider the evolution of the temperature field inside the heavy plate as a specification when planning the entire process that reaches from the slab's exit from the furnace to the last pass.All in all, the production steps of hot rolling govern the plate temperature in two fundamentally different scenarios: sufficiently far from the roll bite, the plate temperature decreases moderately through air cooling or abruptly on the surface of the plate through contact with water which is applied locally in the form of high-pressure jets provided by a water descaling unit. Inside the roll bite, the plastic deformation is accompanied by heat generation inside the plate, and simultaneously the contacting cooler work rolls reduce the temperature at its surfaces. These and other thermomechanical effects can hardly be measured, which is the reason why models are utilized for better insight. As digital transformation has become a significant innovation driver, a digital representation of the process in the form of an integrated digital model, digital shadow, or digital twin has to cover these potentially interfering thermomechanical aspects. [3,4] Modeling and simulation have been integral to the research and development of rolling processes for decades. An incomplete but representative selection of milestones, in chronological order, is intended to outline the road to comprehensive modeling approaches available today: The journey started with basic

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