Characterization of surface properties of a solid plate using nonlinear Lamb wave approach
1Department of Physics, Logistics Engineering University, No. 174, Chang Jiang 2 Road, Chongqing 400016, People's Republic of China. dengmx65@yahoo.com <dengmx65@yahoo.com>
Ultrasonics
|June 27, 2006
Summary
This study introduces a nonlinear Lamb wave method to assess solid plate surface properties without direct contact. Changes in surface characteristics significantly impact second-harmonic generation, enabling effective material characterization.
Area of Science:
- Materials Science
- Non-destructive Testing
- Acoustics
Background:
- Characterizing solid plate surface properties is crucial for material integrity and performance.
- Traditional methods often require direct transducer contact, limiting applications like inspecting sealed vessels.
- Nonlinear ultrasonic techniques offer potential for non-contact surface evaluation.
Purpose of the Study:
- To develop and validate a nonlinear Lamb wave approach for characterizing solid plate surface properties.
- To investigate the influence of surface property variations on second-harmonic generation (SHG) in Lamb waves.
- To explore the utility of a modified Stress Wave Factor (SWF) for surface characterization.
Main Methods:
- Utilizing nonlinear Lamb wave propagation in a solid plate.
- Simulating surface property changes using coatings of varying areas and thicknesses.
- Measuring amplitude-frequency curves of fundamental and second-harmonic Lamb waves.
- Introducing and applying a second-harmonic Stress Wave Factor (SWF) for Lamb waves.
Main Results:
- Changes in surface properties demonstrably affected the efficiency of second-harmonic generation.
- Lamb wave nonlinearity was essential for observing these surface-induced effects.
- The developed second-harmonic SWF showed promise in quantifying surface property variations.
Conclusions:
- Nonlinear Lamb wave propagation is a viable method for non-contact surface characterization.
- Second-harmonic generation is sensitive to alterations in surface properties.
- The second-harmonic SWF provides an effective metric for assessing changes in solid plate surface characteristics.
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