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We demonstrate an integrated non-destructive inspection methodology that employs the nonlinear ultrasonics-based sideband peak counting (SPC) technique in conjunction with topological acoustics (TA) sensing to comprehensively characterize the acoustic response of steel plates that contain differing levels of damage. By combining the SPC technique and TA, increased sensitivity to defect/damage detection as well as the ability to spatially resolve the presence of defects was successfully established. Towards this end, using a Rockwell hardness indenter, steel plates were subject to one, three and five centrally located indentations respectively. The acoustic response of the plate as a function of number of indentations was examined at a frequency range between 50 kHz and 800 kHz, from which the change in a global geometric phase was valuated. Here, geometric phase is a measure of the topological acoustic field response to the spatial locations of the indentations within the steel plates. The global geometric phase unambiguously showed an increase with increasing number of indentations. In addition, spatial variations in a ‘local’ geometric phase as well as spatial variations in the PC index (SPC-I) were also determined. Spatial variations in both the local geometric phase as well as the SPC-I were particularly significant across the indentations for frequencies below 300 kHz, and by combining the respective spatial variations in the SPC-I and geometric phase, the locations of the indentations were accurately identified. The developed SPC-TA nondestructive method represents a promising technique for detecting and evaluating defects in structural materials.
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Non-destructive evaluation of additively manufactured superalloy IN718 via integrating microfocus X-ray computed tomography and non-linear acoustics
evaluated by the sideband peak counting (SPC) nonlinear acoustics method and suitably validated by microfocus X-ray computed tomography (XCT). A wide-band chirp acoustic wave was used to inspect the microstructures of IN718 samples with five distinct process parameters, and the results reveal that the number of sidebands, which result from the non-linearity induced by porosity, is significantly influenced by the distribution and size of pores, in addition to the volume fraction. There was a clear correlation between extent of porosity and the corresponding value of the SPC index. XCT analysis corroborated these findings, providing quantitative insights into the porosity characteristics that affect the ensuing acoustic responses. The findings demonstrated that the porosity with varying sizes and distributions generate different SPC profiles, which were correlated to XCT results to quantitatively assess the size and spatial distributions of the porosity. Fusion of SPC and XCT characterization techniques provides a new strategic approach for non-destructive testing, where the SPC method offers rapid, qualitative evaluation, while XCT provides detailed spatial resolution for defect quantification. The integration of SPC could lead to the development of more cost-effective and advanced quality control protocols, ensuring the reliability of AM-manufactured components regardless of their geometry and composition.
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- Award ID(s):
- 2242925
- PAR ID:
- 10624042
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Additive Manufacturing
- Volume:
- 96
- Issue:
- C
- ISSN:
- 2214-8604
- Page Range / eLocation ID:
- 104539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.addma.2024.104539
