Abstract: In the method for determining the depth of hardening dH, a predefinable number of at least 5 pulses of transverse ultrasonic waves are coupled into a component at a surface of the component. An individual pulse has at least one oscillation period. Between the individual pulses, the variance in the amplitude heights of ultrasonic waves backscattered or reflected back from the component is detected, during which the propagation time tL of the ultrasonic waves is determined. The difference between maxima and minima of the determined variances of the ultrasonic waves following the in-coupling is then formed, this value being multiplied by a factor between >0 and 1 and the product being summed with the minimum of the determined variances.

Abstract: An RFID-based sensing system includes a piezoelectric arrangement mountable at least partially on a structure, an RFID transponder connected to the piezoelectric arrangement, and an antenna connected to the RFID transponder and/or being integrated into the RFID transponder. The piezoelectric arrangement and/or the RFID transponder are adapted to convert kinetic energy provided by the structure into electrical energy usable for powering the RFID transponder and to generate sensing information with respect to a state of the structure. The RFID-based sensing system also includes an RFID reader.

Abstract: Disclosed is a method for the nondestructive metal characterization and the measurement of stress in the interior of a ferromagnetic part under test by means of measuring a high-frequency electric signal caused by flowing an excitation current through the part under test and/or by the mechanical deformation of the part under test. The present invention is distinguished by the electric potential of the part under test being detected by means of direct or indirect electric tapping on said part under test or a region of said part under test and a high-frequency potential component, which is used as the high-frequency noise signal for determining test parameters, is determined from the electric potential of the part under test caused by changes in magnetization processes.