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Title: Non-destructive evaluation of impact damage on carbon fiber laminates: Comparison between ESPI and Shearography

Abstract

The aim of this paper is to investigate the ability of two different interferometric NDT techniques to detect and evaluate barely visible impact damage on composite laminates. The interferometric techniques allow to investigate large and complex structures. Electronic Speckle Pattern Interferometry (ESPI) works through real-time surface illumination by visible laser (i.e. 532 nm) and the range and the accuracy are related to the wavelength. While the ESPI works with the “classic” holographic configuration, that is reference beam and object beam, the Shearography uses the object image itself as reference: two object images are overlapped creating a shear image. This makes the method much less sensitive to external vibrations and noise but with one difference, it measures the first derivative of the displacement. In this work, different specimens at different impact energies have been investigated by means of both methods. The delaminated areas have been estimated and compared.

Authors:
;  [1]; ;  [2]; ;  [3]
  1. CNR National Research Council, ISASI, Institute of Applied Sciences and Intelligent Systems, via Campi Flegrei 34, 80078 Pozzuoli, NA (Italy)
  2. Dpt. Of Chemicals, Materials and Production Engin., University of Naples “Federico II”, P.leTecchio 80, Naples (Italy)
  3. CNR National Research Council, IPCB, Institute of Polymer Composites and Biomedical Materials, P.E. Fermi, Portici (Italy)
Publication Date:
OSTI Identifier:
22608638
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1740; Journal Issue: 1; Conference: 12. international A.I.VE.LA. Conference on vibration measurements by laser and noncontact techniques: Advances and applications, Ancona (Italy), 29 Jun - 1 Jul 2016; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACCURACY; BEAMS; CARBON; CARBON FIBERS; COMPARATIVE EVALUATIONS; CONFIGURATION; DAMAGE; HOLOGRAPHY; ILLUMINANCE; IMAGES; INTERFEROMETRY; LASER RADIATION; NOISE; SURFACES; WAVELENGTHS

Citation Formats

Pagliarulo, V., E-mail: v.pagliarulo@isasi.cnr.it, Ferraro, P., Lopresto, V., Langella, A., Antonucci, V., and Ricciardi, M. R.. Non-destructive evaluation of impact damage on carbon fiber laminates: Comparison between ESPI and Shearography. United States: N. p., 2016. Web. doi:10.1063/1.4952661.
Pagliarulo, V., E-mail: v.pagliarulo@isasi.cnr.it, Ferraro, P., Lopresto, V., Langella, A., Antonucci, V., & Ricciardi, M. R.. Non-destructive evaluation of impact damage on carbon fiber laminates: Comparison between ESPI and Shearography. United States. doi:10.1063/1.4952661.
Pagliarulo, V., E-mail: v.pagliarulo@isasi.cnr.it, Ferraro, P., Lopresto, V., Langella, A., Antonucci, V., and Ricciardi, M. R.. 2016. "Non-destructive evaluation of impact damage on carbon fiber laminates: Comparison between ESPI and Shearography". United States. doi:10.1063/1.4952661.
@article{osti_22608638,
title = {Non-destructive evaluation of impact damage on carbon fiber laminates: Comparison between ESPI and Shearography},
author = {Pagliarulo, V., E-mail: v.pagliarulo@isasi.cnr.it and Ferraro, P. and Lopresto, V. and Langella, A. and Antonucci, V. and Ricciardi, M. R.},
abstractNote = {The aim of this paper is to investigate the ability of two different interferometric NDT techniques to detect and evaluate barely visible impact damage on composite laminates. The interferometric techniques allow to investigate large and complex structures. Electronic Speckle Pattern Interferometry (ESPI) works through real-time surface illumination by visible laser (i.e. 532 nm) and the range and the accuracy are related to the wavelength. While the ESPI works with the “classic” holographic configuration, that is reference beam and object beam, the Shearography uses the object image itself as reference: two object images are overlapped creating a shear image. This makes the method much less sensitive to external vibrations and noise but with one difference, it measures the first derivative of the displacement. In this work, different specimens at different impact energies have been investigated by means of both methods. The delaminated areas have been estimated and compared.},
doi = {10.1063/1.4952661},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1740,
place = {United States},
year = 2016,
month = 6
}
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