Pressure influence on elastic wave attenuation in polycrystalline materials
Christopher M Kube1, Andrea P Arguelles1
1Department of Engineering Science and Mechanics, The Pennsylvania State University, 212 Earth and Engineering Sciences Building, University Park, Pennsylvania 16801, USA.
The Journal of the Acoustical Society of America
|January 3, 2020
Summary
This study models how pressure affects elastic wave attenuation in polycrystalline materials. The findings reveal that pressure
Area of Science:
- Solid Mechanics
- Materials Science
- Acoustics
Background:
- The acoustoelastic effect traditionally describes stress's impact on elastic wave phase velocity (real part of wave number).
- The influence of stress on wave dissipation (imaginary part of wave number) remains less explored.
- Understanding wave attenuation under pressure is crucial for material characterization.
Purpose of the Study:
- To model the influence of pressure on elastic wave attenuation in polycrystalline materials.
- To extend existing attenuation models by incorporating the constitutive behavior of initially stressed solids.
- To investigate the relationship between pressure, wave attenuation, and material elastic properties.
Main Methods:
- Coupling the constitutive behavior of initially stressed solids with Weaver's scattering-based attenuation model.
- Developing a model to predict pressure-dependent longitudinal and shear wave attenuation coefficients.
- Analyzing the dependence of pressure effects on single-crystal elastic anisotropy.
Main Results:
- Derived pressure-dependent longitudinal and shear wave attenuation coefficients for polycrystalline materials.
- Demonstrated that pressure's influence on attenuation is linked to the anisotropy of third-order (nonlinear) elastic constants.
- Showed that stress-free attenuation depends on linear elastic anisotropy.
Conclusions:
- The pressure-induced changes in elastic wave attenuation are critically dependent on the material's nonlinear elastic anisotropy.
- Established a connection between pressure derivatives of velocity and attenuation with fundamental material properties.
- The model highlights the importance of both linear and nonlinear elastic properties, crystal structure, and atomic bonding in determining wave propagation under pressure.
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