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Updated: Oct 19, 2025
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Activating Molecules, Ions, and Solid Particles with Acoustic Cavitation
Published on: April 11, 2014
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Theory of Acoustic Emission From Phase Transformations
1National Bureau of Standards, Washington, DC 20234.
Journal of Research of the National Bureau of Standards (1977)
|September 27, 2021
Summary
This study presents a theoretical framework to predict acoustic emissions during phase transformations. The developed model aids in understanding material behavior and interpreting experimental data from transformations like those in steels.
Area of Science:
- Solid State Physics
- Materials Science
- Acoustics
Background:
- Phase transformations involve changes in crystal structure and material density.
- Acoustic emission is a phenomenon that generates elastic waves during material deformation or transformation.
- Predicting acoustic emission fields requires a robust theoretical framework.
Purpose of the Study:
- To develop a theoretical framework for predicting the dynamic elastic displacement field (acoustic emission) during phase transformations.
- To provide a method for interpreting experimental acoustic emission data from phase transformations.
Main Methods:
- Development of an integral equation for acoustic emission displacement fields from inhomogeneous inclusions.
- Solving the integral equation using multipolar expansion of the source.
- Application of the Eshelby equivalent inclusion method to estimate dynamic multipolar coefficients.
- Explicit calculation of elastic radiation source expressions for spherical and ellipsoidal inclusions.
Main Results:
- A theoretical framework capable of predicting acoustic emission during phase transformations with changes in elastic constants and density.
- Explicit expressions for the elastic radiation source for small isotropic inclusions within an isotropic matrix.
- Demonstrated qualitative interpretation of experimental data from martensitic transformations in steels.
Conclusions:
- The developed theoretical framework provides a basis for understanding acoustic emission during phase transformations.
- Quantitative acoustic emission measurements can yield valuable information about transformation dynamics.
- The model is applicable to interpreting experimental results and guiding future research in materials science.
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