This paper describes an experimental and analytical study on the cryogenic fracture behavior of CFRP-woven laminates under tension with a sharp notch. Single-Edge Notched Tension (SENT) tests were performed at room temperature, liquid nitrogen temperature (77 K), and liquid helium temperature (4 K). During the SENT tests, AE method was implemented to assist in identifying the occurrence of damage which forms from a notch. The growth of crack from notch tip was characterized by microscopical observation and AE response. A finite element analysis was also carried out to calculate the strain energy release rate and stress intensity factor for SENT specimens. The results of the finite element analysis are used to supplement the experimental data. An example is given to show how the acoustic emission data obtained on SENT specimens can be used to nondestructively test the fracture properties of CFRP-woven laminates at low temperatures.
1. Hydenreich, R. (1998). Cryotank in Future Vehicles, Cryogenics, 38(1): 125–130.
2.
2. Sumrall, J., Lane, C. and Cusic, R. (1999). VenturestarTM – Reaping the Benefits of the X-33 Program, Acta Astronautica, 44(7–12): 727–736.
3.
3. Kasen, M.B. (1981). Cryogenic Properties of Filamentary-reinforced Composites: An Update, Cryogenics, 21(6): 323–340.
4.
4. Schutz, J.B. (1998). Properties of Composite Materials for Cryogenic Applications, Cryogenics, 38(1): 3–12.
5.
5. Shindo, Y., Wang, R., Horiguchi, K. and Ueda, S. (1999). Theoretical and Experimental Evaluation of Double-notch Shear Strength of G-10CR Glass-cloth/epoxy Laminates at Cryogenic Temperatures, ASME J. Eng. Mater. Technol., 121(3): 367–373.
6.
6. Shindo, Y., Wang, R. and Horiguchi, K. (2001). Analytical and Experimental Studies of Short-beam Interlaminar Shear Strength of G-10CR Glass-cloth/epoxy Laminates at Cryogenic Temperatures, ASME J. Eng. Mater. Technol., 123(1): 112–118.
7.
7. Shindo, Y., Horiguchi, K., Wang, R. and Kudo, H. (2001). Double Cantilever Beam Measurement and Finite Element Analysis of Cryogenic Mode I Interlaminar Fracture Toughness of Glass-cloth/epoxy Laminates, ASME J. Eng. Mater. Technol., 123(2): 191–197.
8.
8. Horiguchi, K., Shindo, Y., Kudo, H. and Kumagai, S. (2002). End-notched Flexure Testing and Analysis of Mode II Interlaminar Fracture Behavior of Glass-cloth/epoxy Laminates at Cryogenic Temperatures, ASTM J. Compos. Technol. Res., 24(4): 239–245.
9.
9. Kumagai, S., Shindo, Y., Horiguchi, K. and Takeda, T.Mechanical Characterization of CFRP Woven Laminates between Room Temperature and 4 K, JSME Int. J. Ser. A, 46(3): 359–364.
10.
10. Takeda, T., Shindo, Y., Narita, F. and Kumagai, S. (2002). Thermoelastic Analysis of Cracked Woven GFRP Laminates at Cryogenic Temperatures, Cryogenics, 42(8): 451–462.
11.
11. Ni, Q.Q. and Jinen, E. (1993). Acoustic Emission and Fracture of Carbon Fiber Reinforced Thermosoftening Plastic (CFRTP) Materials under Monotonous Tensile Loading, Eng. Fract. Mech., 45(5): 611–625.
12.
12. Qi, G. and Barhorst, A.A. (1997). On Predicting the Fracture Behavior of CFR and GFR Composites using Wavelet-based AE Technique, Eng. Fract. Mech., 58(4): 363–385.
13.
13. Shahid, I., Sun, H.T. and Chang, F.G. (1995). Predicting Scaling Effect on the Notched Strength of Prepreg and Fiber Tow-placed Laminated Composites, J. Compos. Mater., 29(8): 1063–1095.
14.
14. Khashaba, U.A. (2003). Fracture Behavior of Woven Composites Containing Various Cracks Geometry, J. Compos. Mater., 37(1): 5–20.
15.
15. Yuan, F.G. and Yang, S. (2001). Fracture Behavior of Stitched Warp-knit Fabric Composites, Int. J. Fract., 108(1): 73–94.
16.
16. Hinton, M.J., Kaddour, A.S., and Soden, P.D. (2002). Evaluation of Failure Prediction in Composite Laminates: Background to ‘Part B’ of the Exercise, Compos. Sci. Technol., 62(12–13): 1481–1488.
17.
17. Jinen, E. (1990). The Fracture Energy and Acoustic Emission of a Short Carbon Fiber Reinforced Nylon 66 Composite, Eng. Fract. Mech., 37(6): 1183–1194.
18.
18. Sethuraman, R. and Maiti, S.K. (1988). Finite Element based Computation of Strain Energy Release Rate by Modified Crack Closure Integral, Eng. Fract. Mech., 30(2): 227–231.
19.
19. Sih, G.C., Paris, P.C. and Irwin, G.R. (1965). On Cracks in Rectilinearly Anisotropic Bodies, Int. J. Fract. Mech., 1: 189–203.
20.
20. Suzuki, M., Sun, F., Morohashi, S. and Kida, S. (1992). A Study on Fracture Mechanism of Plain Woven Carbon Fabric Compoiste by Acoustic Emission Method (Estimation of Debonding of Fiber/matrix and Transverse/longitudinal Fibers), J. Soc. Mater. Sci., Japan, 41(464): 707–713.
21.
21. Kriz, R.D. and Muster, W.J. (1985). Mechanical-damage Effect in Woven Composites at Low Temperatures, Material Studies for Magnetic Fusion Energy Applications at Low Temperatures-VIII, NBSIR 85– 3025: 49–86.
22.
22. Takeda, T., Shindo, Y., Narita, F. and Sanada, K., Stress Intensity Factors for Woven Glass/ Epoxy Laminates with Cracks at Cryogenic Temperatures, Mech. Adv. Mater. Struct., in press.
