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Microparticle Manipulation by Standing Surface Acoustic Waves with Dual-frequency Excitations
Published on: August 21, 2018
Harmonic generation of an obliquely incident ultrasonic wave in solid-solid contact interfaces
Taehyung Nam1, Taehun Lee, Chungseok Kim
1Department of Automotive Engineering, Hanyang Univ., Seoul, Republic of Korea.
Ultrasonics
|March 14, 2012
Summary
This study introduces an angle beam reflection method to assess contact acoustic nonlinearity (CAN) in solid-solid interfaces. The new model accurately predicts CAN using ultrasonic waves, overcoming limitations of traditional through-transmission techniques.
Area of Science:
- Materials Science
- Non-Destructive Testing
- Acoustics
Background:
- Conventional contact acoustic nonlinearity (CAN) evaluation uses through-transmission, requiring access to both sides of a structure.
- This limits its application in scenarios like closed cracks where surface access is restricted.
Purpose of the Study:
- To develop and validate an angle beam incidence and reflection technique for evaluating CAN at solid-solid interfaces.
- To overcome the accessibility limitations of conventional through-transmission methods.
Main Methods:
- A theoretical model was developed considering linear and nonlinear contact stiffness for angularly incident ultrasonic waves.
- The model accounts for mode conversion and interface stiffness during wave reflection.
- Experimental validation was performed on A16061-T6 alloy specimens under varying pressures.
Main Results:
- The proposed theoretical model accurately predicts the magnitude of CAN-induced second harmonic waves in reflected ultrasonic waves.
- Experimental results demonstrated good agreement with the theoretical predictions.
- The validity of the oblique incidence model for CAN evaluation was confirmed.
Conclusions:
- The angle beam reflection technique offers a viable alternative for assessing CAN, particularly when through-transmission is not feasible.
- The developed theoretical model provides a reliable framework for predicting nonlinear acoustic behavior at solid-solid interfaces.
- This advancement enhances non-destructive evaluation capabilities for materials and structures.
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