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Local defect resonance of a through-thickness crack
1Institute for Polymer Technology (IKT), University of Stuttgart, Germany.
Ultrasonics
|September 11, 2021
Summary
Local Defect Resonance (LDR) can detect through-thickness cracks in plates. This acoustic resonance method uses edge waves along crack faces, offering new non-destructive testing (NDT) opportunities.
Area of Science:
- Materials Science
- Acoustics
- Non-Destructive Testing (NDT)
Background:
- Local Defect Resonance (LDR) is increasingly used for non-destructive testing (NDT) of planar defects in composites.
- Current research primarily focuses on delaminations and impacts as common composite defects.
Purpose of the Study:
- To investigate the mechanism and characteristics of Local Defect Resonance (LDR) for through-thickness cracks in plates.
- To explore the potential of LDR for acoustic-based damage detection.
Main Methods:
- Experimental analysis of Local Defect Resonance (LDR) in plates with through-thickness cracks.
- Investigation of acoustic wave propagation along crack faces.
Main Results:
- LDR in through-thickness cracks is caused by the resonance of edge waves propagating along the crack faces.
- This resonance exhibits weak field decay, allowing for partial and high-order LDR detection.
- The findings demonstrate LDR's effectiveness in identifying cracks.
Conclusions:
- Local Defect Resonance (LDR) is a viable method for detecting through-thickness cracks in plates.
- The unique properties of edge wave resonance offer significant potential for advanced NDT techniques.
- Acoustic activation of damage using LDR can enhance defect characterization.
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