Laser-based linear and nonlinear guided elastic waves at surfaces (2D) and wedges (1D)
Peter Hess1, Alexey M Lomonosov, Andreas P Mayer
1Institute of Physical Chemistry, University of Heidelberg, D-69120 Heidelberg, Germany.
Ultrasonics
|July 3, 2013
Summary
This study reviews guided elastic waves, including surface acoustic waves (SAWs) and wedge waves (WWs), for material analysis and nondestructive evaluation (NDE). It highlights their nonlinear behaviors and applications in determining material properties and fracture strength.
Area of Science:
- Physics, Acoustics, Materials Science
Background:
- Guided elastic waves, including surface acoustic waves (SAWs) and wedge waves (WWs), exhibit unique propagation characteristics along surfaces (2D) and wedges (1D).
- These waves are crucial for understanding material properties and enabling advanced diagnostic techniques.
Purpose of the Study:
- To discuss the characteristic features and applications of linear and nonlinear guided elastic waves.
- To review laser-based, contact-free excitation and detection methods for these waves.
- To explore the use of guided waves in nondestructive evaluation (NDE) and material characterization.
Main Methods:
- Review of laser-based pump-probe techniques for excitation and detection.
- Analysis of broadband surface acoustic waves (SAWs) for material parameter determination.
- Investigation of nonlinear SAWs (solitary and shock waves) and wedge waves (WWs).
Main Results:
- Nonlinear SAWs can be realized as solitary or shock waves, enabling fracture strength determination.
- Dispersion-free and dispersive wedge waves (WWs) were observed, with the latter affected by wedge modifications.
- Theoretical and experimental data on nonlinear wedge waves in various solid types were presented.
Conclusions:
- Guided elastic waves, particularly nonlinear variants, offer powerful tools for NDE and material science.
- Laser-based methods provide effective contact-free analysis capabilities.
- Further research into nonlinear wedge waves can enhance material diagnostics and understanding.
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