A Study on the Fracture Behavior of Laminated Carbon/Epoxy Composite by Acoustic Emission

음향방출법을 이용한 적층복합재료의 파괴거동 연구

  • Received : 2010.01.04
  • Accepted : 2010.03.16
  • Published : 2010.06.15

Abstract

In this study, DAQ and TRA modules were applied to the CFRP single specimen testing method using AE. A method for crack identification in CFRP specimens based on k-mean clustering and wavelet transform analysis are presented. Mode I on DCB under vertical loading and mode II on 3-points ENF testing under share loading have been carried out, thereafter k-mean method for clustering AE data and wavelet transition method per amplitude have been applied to investigate characteristics of interfacial fracture in CFRP composite. It was found that the fracture mechanism of Carbon/Epoxy Composite to estimate of different type of fractures such as matrix(epoxy resin) cracking, delamination and fiber breakage same as AE amplitude distribution using a AE frequency analysis. In conclusion, the presented results provide a foundation for using wavelet analysis as efficient crack detection tool. The advantage of using wavelet analysis is that local features in a displacement response signal can be identified with a desired resolution, provided that the response signal to be analyzed picks up the perturbations caused by the presence of the crack.

Keywords

References

  1. Mehan, R. L. and Mullin, J. V., "Analysis of Composite Failure Mechanisms Using Acoustic Emissions," Journal of Composite Materials, Vol. 5, pp. 266-269, 1971. https://doi.org/10.1177/002199837100500213
  2. Zimmer, J. E., "Fracture Mechanics of a Fiber Composite," Journal of Composite Materials, Vol. 6, pp. 312-315, 1972. https://doi.org/10.1177/002199837200600213
  3. Adams, R. D. and Flitcroft, J. E., "Effect of Shear Damage on the Torsional Behaviour of Carbon Fibre Reinforced Plastics," Journal of Composite Materials, Vol. 7, pp. 68-75, 1973. https://doi.org/10.1177/002199837300700105
  4. Yang, J. N. and Du, S., "An Exploratory Study into the Fatigue of Composites Under Spectrum Loading," Journal of Composite Materials, Vol. 17, pp. 511-526, 1983. https://doi.org/10.1177/002199838301700604
  5. Radhakrishnan, K., "Fatigue and Reliability Evaluation of Unnotched Carbon Epoxy Laminates," Journal of Composite Materials, Vol. 18, pp. 21-31, 1984. https://doi.org/10.1177/002199838401800102
  6. Soutis, C., Fleck, N. A., and Smith, P. A., "Failure Prediction Technique for Compression Loaded Carbon Fibre-Epoxy Laminate with Open Holes," Journal of Composite Material, Vol. 25, pp. 1476-1498, 1991. https://doi.org/10.1177/002199839102501106
  7. Lee, T. S., Choi, Y. G., and Chang, C. W., "A Study on Characteristics of lnterlaminar Fracture Toughness and Fatigue Crack Propagation for Carbon/Epoxy Composites," Transactions of the KSME Series A, Vol. 21, No. 4, pp. 566-574, 1997.
  8. Yoon, J. H., Park, S.O., Rhee, Z. K., and Woo, C. K., "A study on the fracture characteristics of CFRP by AE," Proceeding of KSTME fall conference, pp. 283-288, 2003.
  9. Adams, D. F., Carlsson, L. A., and Pipes, R. B., "Experimental Characterization of Advanced Composite Materials, 3rd Edition, CRC Press," 2003.
  10. ASTM Standard D5528-94a, 2001, Test Method for Mode I Interlaminar Fracture Toughness of Unidirectional Fiber-Reinforced Polymer Matrix Composites, American Society for Testing and Materials, West Conshohocken, PA.
  11. Japanese Industrial Standards JIS 7086, 1993, Testing Methods for Interlaminar Fracture Toughness of Carbon Fiber Reinforced Plastics, Japanese Standards Association, Tokyo, Japan.