Simulation of IMPOC system for online monitoring of steel mechanical properties

Reboud, Christophe; CEA LIST; France

Skarlatos, A.; CEA; France
Reboud, C.; CEA, LIST; France
Kebe, T.; ThyssenKrupp Steel Europe; Germany
van den Berg, F.D.; Tata Steel; Netherlands
Schmidt, R.; Arcelor-Mittal Eisenhüttenstadt; Germany

ID: ECNDT-0258-2018
Download: PDF
Session: Modeling and data processing Electromagnetic Techniques 1
Room: J2
Date: 2018-06-12
Time: 09:20 - 09:40

The IMPOC system is a broadly applied device in steel industry for the online assessment of steel strip’s mechanical properties. It carries out non-destructive electromagnetic measurements that are very well correlated with properties like tensile strength and yield strength, for instance. The measurement is however not only sensitive to the electromagnetic properties of the steel strip under investigation, but it is also influenced by other factors, like the strip thickness, its speed variations, and the lift-off separating it from the IMPOC system. To mitigate those effects, some empirical compensation functions are introduced (in the case of strip speed in particular) as a post-processing. The use of accurate modelling tools enables to better understand the various effects and allows the theoretical calculations of compensation coefficients.

CEA LIST has developed, within the Product Uniformity Control project, a 2D numerical model based on the Finite Integration Technique (FIT) dedicated to IMPOC simulation. Besides the strategy for solving non linear problems and managing magnetic hysteresis in the solver, several parametric models have been implemented in order to describe the B(H) relation and fit experimental measurements carried out in laboratory. In this communication, the modelling approach will be presented and its validation with respect to experimental data, provided by partners of the project, will be discussed. Then, detailed simulation results of the influence on IMPOC signals from strip thickness, strip speed and steel grade will be presented. Steel grades considered in these studies are low carbon, interstitial free, micro-alloyed and dual phase steels, at various stages of production, like hot and cold rolling.

This work has been carried out in the context of the European Project Product Uniformity Control (PUC), funded by the RFCS program.