NDT Technology

NDT Technology

Application of the laser shearography in the non-destructive evaluation of the defects in the flat and curved surfaces made of carbon fiber composites

Document Type : Original Article

Authors
Amjad Sazgar 1
Morteza Amiri 2
1 nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute
2 Researcher of AEOI, Tehran – Iran.
10.30494/jndt.2021.266035.1049
Abstract
Laser shearing interferometry or Shearography is one of the new optic methods for calculating the very small surface displacement derivatives in order of microns. Shearography can be beneficially used in the non-destructive testing of materials, especially in composites. In this paper, laser shearography is used to detect some kinds of defects like cavities, solid inclusions and matrix cracks in both flat and curved furnaces made of carbon fiber reinforced composites. As the system parameters and loading amount are the most important factors affecting defect detection ability in this technique, the test scenarios including all these factors have been compiled for both flat and curved surfaces. The shearography tests are performed to get the best results of defect detectability in the test specimens. The results show that the best responses are observed with a shear size of one half the approximated defect sizes. The thermal loading range of 3kW and 1kW in the 0.5 and 1 seconds should be used as the best choices in the flat sheet and curved sheet specimens respectively.
Keywords
Laser Shearing interferometry
Digital shearography
Non-destructive inspection
Polymer matrix material
Sub-surface defects

Subjects

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[3]     J. Leendertz, J. Butters, An image sharing speckle pattern interferometer for measuring bending moments, Journal of Physics E., 6 [1], 1017 (1973).
[4]     S. L. Toh et al. Application of sheagraphy in nondestructive testing of composite plates, Journal of Materials Processing Technology, 23 [3], 267 (1990).
[5]     D. Akbari, N. Soltani, F. Reshadi, Application of digital shearography for non-destructive testing of materials with thermal loading, Modares Mechanical Engineering, 13 [4], 36 (2013). (in Persian)
[6]     M. Mohamadi, D. Akbari, Evaluation of sub-surface cracks in polymer matrix composites with laser interferometric method, International Journal of Manufacturing Engineering, 2 [3], 11 (2015). (in Persian)

  • Receive Date 05 January 2021
  • Revise Date 13 January 2021
  • Accept Date 15 January 2021