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Abstract

This paper presents an experimental and numerical investigation on the effects of stitching distribution on the interlaminar fracture toughness of carbon fiber reinforced polymers (CFRPs) using an end notch flexure (ENF) specimen. To avoid premature failure in bending, reinforcing tabs were bonded to either side of the ENF specimens to create a tabbed ENF (TENF) specimen. The effect of stitch distribution on mode II delamination toughness is investigated by considering several stitch distribution patterns. The experimental results indicate that the mode II delamination toughness of stitched TENF specimens can be effectively measured and that stitch distribution does not play a significant role in improving the steady-state mode II delamination toughness of stitched CFRPs. Numerical results are also obtained using both MSC/NASTRAN and an in-house software for the tested specimens. A reasonable correlation exists between the numerical and experimental results.

Keywords

stitching ENF mode II delamination toughness reinforcing tabs.

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References

Tong, L. , Mouritz, A.P. and Bannister, M.K. (2002). 3D Fibre Reinforced Polymer Composites. Elsevier Science, Oxford, UK.

Dransfield, K. , Baillie, C. and Mai, Y.-W. (1994). Improving the Delamination Resistance of CFRP by Stitching — A Review. Composites Science and Technology, 50: 305—317.

Mouritz, A.P. , Leong, K.H. and Herszberg , I. (1997). A review of the Effects of Stitching on the In-plane Mechanical Properties of Fibre-reinforced Polymer Composites. Composites Part A, 28A: 979—991.

Astm D5528-01 (2001). Standard Test Method for Mode I Interlaminar Fracture Toughness of Unidirectional Fiber-Reinforced Polymer Matrix Composites.

Jain, L.K. , Dransfield, K.A. and Mai, Y.-W. (1998). Effect of Reinforcing Tabs on the Mode I Delamination Toughness of Stitched CFRPs. Journal of Composite Materials , 32(22): 2016—2026.

Guenon, V.A. , Chou, T.W. and Gillespie , J.W. (1989). Toughness Properties of a 3-Dimensional Carbon Epoxy Composite. Journal of Materials Science, 24(11): 4168—4175.

Rong, M.Z. , Zhang, M.Q. , Liu, Y. , Zhang, Z.W. , Yang, G.C. and Zeng, H.M. (2002). Effect of Stitching on In-plane and Interlaminar Properties of Sisal/Epoxy Laminates. Journal of Composite Materials, 36(12): 1505—1526.

Astm (1990), A Protocol for Interlaminar Fracture Testing, Mode II. ASTM Standard.

Jain, L.K. and Mai, Y.-W. (1994). On the Effect of Stitching on Mode I Delamination Toughness of Laminated Composites. Composites Science and Technology, 51: 331—345.

10.

Jain, L.K. and Mai, Y.-W. (1995). Determination of Mode II Delamination Toughness of Stitched Laminated Composites. Composites Science and Technology , 55: 241—253.

11.

Jain, L.K. and Mai, Y.-W. (1994). Analysis of Stitched Laminated ENF Specimens for Interlaminar mode II Fracture Toughness. International Journal of Fracture, 68: 219—244.

12.

Sun, X. , et al. (2004). Effect of Stitch Distribution on mode I Delamination Toughness of Laminated DCB Specimens. Composites Science and Technology, 64: 967—981.

13.

Hibbeler, R.C. (1997). Mechanics of Materials , 3rd ed. Prentice Hall International, Inc.

14.

Chatterjee, S.N. (1991). Analysis of Test Specimens for Interlaminar Mode II Fracture Toughness, Part 1. Elastic Laminates. Journal of Composite Materials, 25: 470—493.

15.

Gibson, R.F. (1994). Principles of Composite Material Mechanics, Holman, J.P. and Lloyd, J.R. eds., McGraw-Hill Book Co.

16.

Msc (2005). Nastran 2005: Quick Reference Guide.

17.

Rybicki, E.F. and Kanninen, M.F. (1977). A Finite Element Calculation of Stress Intensity Factors by a Modified Crack Closure Integral. Engineering Fracture Mechanics, 9: 931—938.

18.

Aymerich, F. , Onnis, R. and Priolo, P. (2005). Analysis of the Fracture Behaviour of a Stitched Single-lap Joint. Composites Part A — Applied Science and Manufacturing, 36(5): 603—614.

19.

Tan, P. , Tong, L. and Steven, G.P. (1998). Modeling Approaches for 3D Orthogonal Woven Composites . Journal of Reinforced Plastics and Composites, 17(6): 545—577.

A New ENF Test Specimen for the Mode II Delamination Toughness Testing of Stitched Woven CFRP Laminates

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