EUROPEAN STEEL TECHNOLOGY AND APPLICATION DAYS 2017 - ESTAD 2017

Inline measurement of mechanical and magnetic properties of steel strip with contactless, non-destructive techniques offers considerable potential for further technological optimization and new applications. This is achieved by the PropertyMon system from Primetals Technologies employing state-of-the-art methods for indirect measurements using electromagnetic signals. By measuring the hysteresis curve of the steel strip, mechanical and magnetic properties can be calculated applying regression calculations. The required coefficients are obtained via regression analysis of test measurements and corresponding laboratory samples. This method gives reliable results for e.g. tensile strength, yield strength, hardness, magnetic losses and magnetic polarization. Recently, test trials to determine magnetic power losses P and polarization J were carried out at an annealing line of thyssenkrupp Steel Europe in Bochum, Germany, for non-grain oriented (NO) electrical steel. This article presents test results for these magnetic parameters which are of importance especially for electrical steel strip production processes. Continuous calculations of P and J can be achieved with a high degree of accuracy for online process monitoring and quality control. Remarkably, the PropertyMon system exhibits some unique features such as the simultaneous detection of mechanical and magnetic properties, directional measurements for anisotropic properties, and space-resolved measuring via traversing of compact sensors over the strip width. Therefore, this approach complements or outperforms standardized destructive laboratory testing procedures in many ways.