Early detection of fatigue cracks in truck trailer structures by acoustic emission testing

Klemm, Rolf; Institut für Theoretische Elektrotechnik und Mikroelektronik - University of Bremen; Germany

Klemm, R.; University of Bremen; Germany
Pimentel, J.V.; University of Bremen; Germany
Irretier, A.; University of Bremen; Germany
Dalgic, M.; University of Bremen; Germany
Krieger, K.-L.; University of Bremen; Germany

ID: ECNDT-0351-2018
Download: PDF
Session: Transportation, railway & automotive 1
Room: R2
Date: 2018-06-13
Time: 13:30 - 13:50

In fatigue tests, acoustic emission can be measured when cracks occur. In this work the equivalent stresses on a test specimen, modelled after a section of a truck trailer, are calculated using FEA. This information is used to determine the position with the highest probability of a crack occurring. After performing a series of fatigue tests to generate a Wöhler diagram and recording acoustic emissions, an adaptive filter for processing the signal data is presented. In a further experiment, a sample is tested in a fatigue test until acoustic emissions can be detected with the help of the presented signal processing. Further, the resulting crack is examined by preparation of a microsection. Subsequent analysis of the samples strongly indicate that the AE detection algorithms were indeed able to detect microfractures well in advance of the occurrence of failures. In this paper, the accuracy of the detections is discussed by comparing their results with those from the metallographic and microscopic examinations of the tested samples. The use of external variables to validate the detections is also presented, as well as the experimental set-ups and post-processing strategies.