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This work presents numerical modeling-based investigations for detecting and monitoring damage growth and material nonlinearity in plate structures using topological acoustic (TA) and sideband peak count (SPC)-based sensing techniques. The nonlinear ultrasonic SPC-based technique (SPC-index or SPC-I) has shown its effectiveness in monitoring damage growth affecting various engineering materials. However, the new acoustic parameter, “geometric phase change (GPC)” and GPC-index (or GPC-I), derived from the TA sensing technique adopted for monitoring damage growth or material nonlinearity has not been reported yet. The damage growth modeling is carried out by the peri-ultrasound technique to simulate nonlinear interactions between elastic waves and damages (cracks). For damage growth with a purely linear response and for the nonlinearity arising from only the nonlinear stress–strain relationship of the material, the numerical analysis is conducted by the finite element method (FEM) in the Abaqus/CAE 2021 software. In both numerical modeling scenarios, the SPC- and GPC-based techniques are adopted to capture and compare those responses. The computed results show that, from a purely linear scattering response in FEM modeling, the GPC-I can effectively detect the existence of damage but cannot monitor damage growth since the linear scattering differences are small when crack thickness increases. The SPC-I does not show any change when a nonlinear response is not generated. However, the nonlinear response from the damage growth can be efficiently modeled by the nonlocal peri-ultrasound technique. Both the GPC-I and SPC-I techniques can clearly show the damage evolution process if the frequencies are properly chosen. This investigation also shows that the GPC-I indicator has the capability to distinguish nonlinear materials from linear materials while the SPC-I is found to be more effective in distinguishing between different types of nonlinear materials. This work can reveal the mechanism of GPC-I for capturing linear and nonlinear responses, and thus can provide guidance in structural health monitoring (SHM).
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This content will become publicly available on July 1, 2026
Resonant Soft X-Ray Scattering in Polymer Materials
Resonant soft X-ray scattering (RSoXS) is a powerful tool for chemically and orientationally resolved nano-to-mesoscale characterization of complex molecular materials. Through its development over the past 15 years, its use has been extended to uniquely characterize structures, not only dry, thin films for devices, coatings, photolithography, and liquid crystalline ordering, but also solvated nanostructures in biology for therapeutics and hydrated membranes for filtration or biosensing. Here, we review progress in this exciting and maturing technique with an eye toward the materials scientist or engineer who has little experience with RSoXS but would like to know more about how the technique would fit into their toolset.
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- Award ID(s):
- 2247711
- PAR ID:
- 10638365
- Publisher / Repository:
- Annual Reviews
- Date Published:
- Journal Name:
- Annual Review of Materials Research
- Volume:
- 55
- Issue:
- 1
- ISSN:
- 1531-7331
- Page Range / eLocation ID:
- 1 to 35
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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