[Zurück]

M. Gröschl, M. Haas, E. Mayrhofer, C. Tscherne:
"Acoustic emission monitoring as a method for the online-investigation of tribological processes; invited keynote paper; eingeladener Plenarvortrag";
Vortrag: 7th AAAA Congress on Sound and Vibration, Ljubljana/Slovenia (eingeladen); 23.09.2016; in: "7th AAAA Congress on Sound and Vibration; editor: M. Cudina", (2016), S. 331 - 338.

Acoustic emission monitoring (AEM) is a well-established non-destructive method to detect and
locate faults in mechanically loaded structures and components. Ultrasonic sensors detect the
acoustic signals generated by material or structural failure. Acoustic emission frequencies are usually
in the kHz frequency range.
The paper reviews the principle, technical aspects and applications of AEM. The AEM signal chain
is introduced, comprising the source (being the material or structure under mechanical stress), the
propagating acoustic wave, the sensor(s), and the signal-conditioning electronics. Issues of sensor
performance and calibration are emphasized and the advantages and limitations of AEM are identified.
Multichannel AEM techniques are explained that allow for the localisation of AEM sources.
Common application fields of AEM are discussed, such as the detection and localisation of crack
formation and crack growth. In addition, recent results are presented on AEM research done at the
Excellence Centre of Tribology, Wiener Neustadt, Austria, in collaboration with the TU Wien. This
work focuses on AEM in the MHz frequency range, which shows high potential for, e.g., the characterisation
of wear processes, including the investigation of the run-in period, as well as the detection
of micro cracks or of delamination of coatings.