High school of Esslingen (Esslingen, Germany):

T. Eisele, Mag. Sci., Scientific researcher, e-mail: tanja.eisele@hs-esslingen.de
H. Lücken, Dr. Eng., Prof., Transport technology faculty

Deutsches Kupferinstitut Berufsverband e. V. (Düsseldorf, Germany):
Ph. Skoda, Dr. Eng., Dept. of Industrial Technologies for Connection of Materials

Abstract: The current state of developments in the field of non-destructive testing of flat rolled steel with an emphasis on formation of oxide layers in a surface layer has been considered. These defects can be easily detected in the laboratory conditions. The challenge is the use of this method in conditions of existing production, taking into account the speed of the strip more than 5 m/s. Operational control methods require a reliable measurement technique that will ensure reliable detection of defects, taking into account the economic efficiency of the method. Areas of application of control methods regarding the characteristics of defects in the surface layer were given. It is seen that the greatest potential for determining the described blister defects has such a control method as thermography. In this regard, the Esslingen Higher School conducts research work on determining blisters using active thermography. The goal is to identify with the help of modeling and experimens the boundaries of application fields of this method and its optimization using the appropriate parameters. Along with interference filtering, the challenge is also high image processing requirements due to the significant amount of information.

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