Evaluation of stress states and mechanical properties of rolled products using electromagnetic and ultrasonic methods

There is profound unterstanding of the physical background of the electromagnetic/ magnetoelastic and ultrasonic techniques to evaluate stress states in components. The strategy towards the appropriate calibration of different electromagnetic/ magneto-elastic quantities for stress analysis is known and proven. The elastic and acoustoelastic constants, needed for the quantitative ultrasonic stress analysis have been evaluated for large number of steel grades and Al-alloys. The investigations of the influences of microstructural states and textures on the electromagnetic/ magnetoelastic and ultrasonic quantities resulted in methods to minimize these influences in case of a stress analysis or to use the measured data to characterize texture and to evaluate material properties like strength and drawability. Sensors and set-ups are developed for practicular cases of application. But, neither the ultrasonic nor the electromagnetic/ magnetoelastic set-ups can just be taken from the shelf and applied. The measuring technique and the lay-out of the sensor have to be adapted to the individual case of application.