Process-Integrated Eddy Current Quality Assurance (Theoretical Simulations, Study, Investigation)

A process-integrated quality assurance for carbon fiber reinforced plastics (CFRP) is nowadays a trending direction. It is known that eddy current impedance spectroscopy working in a radio wave range, also called radio frequency (RF) eddy current (EC), allows detection of electrical and dielectric properties of CFRP and therefore it becomes possible to determine carbon fiber orientations and dielectric matrix defects. However, it is not possible to quantify these defects, which blocks further developing of a process-integrated quality assurance method. Experiments with copper and CFRP test-samples were performed in order to study deeply the contrast picture forming by RF EC. Obtained data was represented and analyzed in MatLab. Methods for contrast enhancing and image processing for mistakes detection based on experimental results are discussed in details in this paper. Moreover, the influence of sensor type, size and orientation on image quality was investigated within this research. Thus, this paper gives an overview of methods for RF EC image contrast formation and processing in order to acquire and quantify the information about type, size and placement of the fiber and matrix errors along the CFRP structure, such as fuzzy balls, missed lines, dry places etc.

  • Non-destructive testing – Eddy Current testing – General principles, ISO 1549, 2008.
  • Heuer H., M. H. Schultze, and N. Meyendorf, “Non-destructive evaluation (NDE) of composites: eddy current techniques,” in Non-destructive evaluation (NDE) of polymer matrix composites: Techniques and applications, edited by V. M. Karbhari (Woodhead Publishing, Cambridge, UK, Philadelfia), pp.33-55, 2013.
  • Heuer H., M. Prof., M. Schulze, S. Pooch, A. Gäbler, G. Nocke, et al., “Review on quality assurance along the CFRP value chain–non-destructive testing of fabrics, preforms and CFRP by HF radio wave techniques”, in Composites Part B: Engineering 77, edited by Elsevier, pp. 494-501, 2015.
  • Sadat, A. B., "Delamination and other types of damage of graphite/epoxy composite caused by machining," Machining of advanced materials, Vol. 41-52, 1995.
  • Liu D., Fleck N.A., Sutcliffe M.P.F. , "Compressive strength of fibre composites with random fibre waviness," Journal of the Mechanics and Physics of Solids, Vol. 52, 1481 – 1505, 2004.
  • Hagemaier D.J. Eddy-current standard depth of penetration. Mater Eval 1985; 43(11):1438-41.
Usage Shares
Total Views
47 Page Views
Total Shares
0 Tweets
0 PDF Downloads
0 Facebook Shares
Total Usage