Journal of Nondestructive Evaluation

, Volume 17, Issue 2, pp 53–65 | Cite as

Quantitative characterization of multiple delaminations in laminated composites using the compton backscatter technique

  • Nohyu Kim
  • J. D. Achenbach


A Compton X-ray backscatter technique was used to supplement ultrasonic pulse-echo C-scan imaging to quantitatively assess the impact damage in quasi-isotropic laminated composites which were impacted by a drop-weight tester. A Compton backscatter imaging system with a slit-type camera was developed to obtain a cross-sectional profile of impact-damaged laminated composites from the density variation of the cross-section. A nonlinear reconstruction model is introduced to overcome distortion of the Compton backscatter image due to attenuation effects, beam hardening, and irregular distributions of the fibers and the matrix in composites. An adaptive filter is used to reduce noise from many sources including quantum noise, especially when the SNR (signal-to-noise ratio) of the image is relatively low. Delaminations masked or distorted by the first few delaminations in an ultrasonic C-scan image are detected and characterized by the Compton back-scatter technique, both in width and location.

Key words

Compton X-ray backscatter ultrasonic C-scan laminated composite impact damage delaminations 


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Copyright information

© Plenum Publishing Corporation 1998

Authors and Affiliations

  • Nohyu Kim
    • 1
  • J. D. Achenbach
    • 1
  1. 1.Center for Quality Engineering and Failure PreventionNorthwestern UniversityEvanston

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