A well-known strength of LUS compared to X-ray or classical ultrasound methods, which are often used for non-destructive testing, is that measurements can be conducted in a non-contact manner and, if necessary, even from a great distance. This advantage, combined with the possibility of efficiently examining samples of all sizes with complex topographical structures for their internal mechanical condition with minimal measurement effort, is the highly innovative result of the present research work recently published by M. Saurer et al. in two relevant scientific journals.1, 2
The basis for the novel approach is given by the simulation results of a realistic model of the entire measurement process, taking into account the specific sample topography. This allows the derivation of promising positions for ultrasonic wave generation and detection in order to reliably detect hidden cavities at which the waves are reflected, with significantly reduced measurement effort. The method was successfully tested for the detection of inclusions in laser welded seams with curved surfaces, which is a typical representative of an industrial application. Many other applications can be envisaged, where a fast, remote and continuous quality inspection is required.
The research project was conducted as part of the IMPROFE project (no.: 883940) funded by the Austrian Research Promotion Agency (FFG).
[1] Markus Saurer, Guenther Paltauf, Robert Nuster, Laser ultrasound wave pattern analysis for efficient defect detection in samples with curved surfaces, Photoacoustics, Volume 40, 2024, 100654, ISSN 2213-5979, https://doi.org/10.1016/j.pacs.2024.100654.
[2] Markus Saurer, Guenther Paltauf, Robert Nuster, Efficient testing of weld seam models with radii of curvature in the millimeter range using laser ultrasound, Ultrasonics, Volume 139, 2024, 107292, ISSN 0041-624X, https://doi.org/10.1016/j.ultras.2024.107292.
Contact information: markus.saurer(at)uni-graz.at and ro.nuster(at)uni-graz.at.