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arXiv · 2206.08934

Experimental determination of Lamb wave dispersion diagrams over large frequency ranges in fiber metal laminates

Tilmann Barth·Johannes Wiedemann·Thomas Roloff·Tim Behrens·Natalie Rauter·Christian Hühne·Michael Sinapius·Rolf Lammering
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Abstract

Fiber metal laminates (FML) are of high interest for lightweight structures as they combine the advantageous material properties of metals and fiber-reinforced polymers. However, low-velocity impacts can lead to complex internal damage. Therefore, structural health monitoring with guided ultrasonic waves (GUW) is a methodology to identify such damage. Numerical simulations form the basis for corresponding investigations, but experimental validation of dispersion diagrams over a wide frequency range is hardly found in the literature. In this work the dispersive relation of GUWs is experimentally determined for an FML made of carbon fiber-reinforced polymer and steel. For this purpose, multi-frequency excitation signals are used to generate GUWs and the resulting wave field is measured via laser scanning vibrometry. The data are processed by means of a non-uniform discrete 2d Fourier transform and analyzed in the frequency-wavenumber domain. The experimental data are in excellent agreement with data from a numerical solution of the analytical framework. In conclusion, this work presents a highly automatable method to experimentally determine dispersion diagrams of GUWs in FML over large frequency ranges with high accuracy.

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Tilmann Barth, Johannes Wiedemann, Thomas Roloff, Tim Behrens, Natalie Rauter, Christian Hühne, Michael Sinapius, Rolf Lammering. 2022-12-08. Experimental determination of Lamb wave dispersion diagrams over large frequency ranges in fiber metal laminates. https://doi.org/10.1088/1361-665x%2Face0ea

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