Advances in aircraft and spacecraft science

  • 제6권2호
  • /
  • Pages.145-156
  • /
  • 2019
  • /
  • 2287-528X(pISSN)
  • /
  • 2287-5271(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Creating damage tolerant intersections in composite structures using tufting and 3D woven connectors

  • Clegg, Harry M. (The National Composites Centre, Bristol & Bath Science Park) ;
  • Dell'Anno, Giuseppe (The National Composites Centre, Bristol & Bath Science Park) ;
  • Partridge, Ivana K. (Bristol Composites Institute, The University of Bristol)
  • 투고 : 2018.10.15
  • 심사 : 2018.01.03
  • 발행 : 2019.03.25
⟨ 이전 논문 다음 논문 ⟩

초록

As the industrial desire for a step change in productivity within the manufacture of composite structures increases, so does the interest in Through-Thickness Reinforcement technologies. As manufacturers look to increase the production rate, whilst reducing cost, Through-Thickness Reinforcement technologies represent valid methods to reinforce structural joints, as well as providing a potential alternative to mechanical fastening and bolting. The use of tufting promises to resolve the typically low delamination resistance, which is necessary when it comes to creating intersections within complex composite structures. Emerging methods include the use of 3D woven connectors, and orthogonally intersecting fibre packs, with the components secured by the selective insertion of microfasteners in the form of tufts. Intersections of this type are prevalent in aeronautical applications, as a typical connection to be found in aircraft wing structures, and their intersections with the composite skin and other structural elements. The common practice is to create back-to-back composite "L's", or to utilise a machined metallic connector, mechanically fastened to the remainder of the structure. 3D woven connectors and selective Through-Thickness Reinforcement promise to increase the ultimate load that the structure can bear, whilst reducing manufacturing complexity, increasing the load carrying capability and facilitating the automated production of parts of the composite structure. This paper provides an overview of the currently available methods for creating intersections within composite structures and compares them to alternatives involving the use of 3D woven connectors, and the application of selective Through-Thickness Reinforcement for enhanced damage tolerance. The use of tufts is investigated, and their effect on the load carrying ability of the structure is examined. The results of mechanical tests are presented for each of the methods described, and their failure characteristics examined.

키워드

참고문헌

  1. Allegri, G. and Zhang, X. (2007), "On the delamination suppression in structural joints by Z-fibre pinning", Compos. Part A Appl. Sci. Manufact., 38, 1107-1115 https://doi.org/10.1016/j.compositesa.2006.06.013
  2. Bianchi, F. (2012), "Finite element modelling of Z-pinned composite T-joints", Compos. Sci. Technol., 73, 48-56. https://doi.org/10.1016/j.compscitech.2012.09.008
  3. Bigaud, J. (2018), "Analysis of the mechanical behaviour of composite T-joints reinforced by one sided stitching", Compos. Struct., 184, 249-255. https://doi.org/10.1016/j.compstruct.2017.06.041
  4. Broughton, W.R. (2002), "Design requirements for bonded and bolted composite structures", NPL Report MATC(A)65; National Physical Laboratory, United Kingdom.
  5. Burns, L. (2012), "Bio-inspired design of aerospace composite joints for improved damage tolerance", Compos. Struct., 94(3), 995-1004. https://doi.org/10.1016/j.compstruct.2011.11.005
  6. Cartie, D.D.R. (2006), "3D reinforcement of stiffener-to-skin t-joints by z-pinning and tufting", Eng. Fracture Mech., 73(16), 2532-2540. https://doi.org/10.1016/j.engfracmech.2006.06.012
  7. Clegg, H.M., Kratz, J.K., Partridge, I.K. and Dell'Anno, G. (2016), "Evaluation of the effects of tufting on performance of composite T-joints", Proceedings of the 17th European Conference on Composite Materials, June, Munich.
  8. Cullinan, J.F. (2016), "Damage manipulation and in situ repair of composite T-joints", J. Aircraft, 53, 1013-1021. https://doi.org/10.2514/1.C033627
  9. Dell'Anno, G., Treiber, J.W.G. and Partridge, I.K. (2016), "Manufacturing of parts reinforced throughthickness by tufting", Robotics Comput.-Integrated Manufact., 37, 262-272. https://doi.org/10.1016/j.rcim.2015.04.004
  10. Dell'Anno, G. (2007), "Effect of tufting on the mechanical behaviour of carbon fabric epoxy composites", Ph. D. Dissertation, Cranfield University, United Kingdom.
  11. Dransfield, K. and Baillie, C. (1994), "Improving the delamination resistance of CFRP by stitching - A review", Compos. Sci. Technol., 50(3), 305-317. https://doi.org/10.1016/0266-3538(94)90019-1
  12. Greenhalgh, E. (2003), "The assessment of novel materials and processes for the impact tolerant design of stiffened composite aerospace structures", Compos. Part A, 34, 151-161. https://doi.org/10.1016/S1359-835X(02)00188-4
  13. Greenhalgh, E.S. (2006), "Evaluation of toughening concepts at structural features in CFRP Part I: Stiffener pull-off", Compos. Part A, 37, 1521-1535. https://doi.org/10.1016/j.compositesa.2005.11.009
  14. Kratz, J., Clegg, H.M., Dell'Anno, G. and Partridge, I.K. (2015), "Improving the damage tolerance of composite joints with tufting", Proceedings of the 20th International Conference on Composite Materials, July, Copenhagen.
  15. Martins, A.T. (2019), "Structural health monitoring for GFRP composite by the piezoresistive response in the tufted reinforcements", Compos. Struct., 209, 103-111. https://doi.org/10.1016/j.compstruct.2018.10.091
  16. Mouritz, A.P. (1997), "A review of the effect of stitching on the in-plane mechanical properties of fibrereinforced polymer composites", Compos. Part A, 28, 979-991. https://doi.org/10.1016/S1359-835X(97)00057-2
  17. Mouritz, A.P. (2010), "Design dilemma for Z-pinned composite structures", 27th International Congress of the Aeronautical Sciences 2010, September, Nice.
  18. Osmiani, C. (2016), "Exploring the influence of micro-structure on the mechanical properties and crack bridging mechanisms of fibrous tufts", Compos. Part A, 91, 409-419. https://doi.org/10.1016/j.compositesa.2016.08.008
  19. Partridge, I.K. and Hallett, S.R. (2016), "Use of microfasteners to produce damage tolerant composite structures", Philos. T. R. Soc. A, 374, 20150277. https://doi.org/10.1098/rsta.2015.0277
  20. Scott, M., Dell'Anno, G. and Clegg, H.M. (2018), "Effect of process parameters on the geometry of composite parts reinforced by through-the-thickness tufting", Appl. Compos. Mater., 25(4), 785-796. https://doi.org/10.1007/s10443-018-9710-4
  21. Stickler, P.B. (2001), "Investigation of mechanical behaviour of transverse stitched T-joints with PR520 resin in flexure and tension", Compos. Struct., 52(3-4), 307-314. https://doi.org/10.1016/S0263-8223(01)00023-X
  22. Tan, K.T. (2013), "Effect of stitch density and stitch thread thickness on damage progression and failure characteristics of stitched composites under out-of-plane loading", Compos. Sci. Technol., 74, 194-204. https://doi.org/10.1016/j.compscitech.2012.11.001
  23. Tomblin, J.S. and Salah, L. (2017), "Teardown evaluation of a composite carbon epoxy beechcraft starship aft wing", DOT/FAA/TC-15/47; Federal Aviation Administration, William J. Hughes Technical Center, Aviation Research Division, Atlantic City, U.S.A.
  24. Vazquez, J.T. (2011), "Multi-level analysis of low-cost Z-pinned composite joints part 1: Single Z-pin behaviour", Compos. Part A, 42, 2070-2081. https://doi.org/10.1016/j.compositesa.2011.09.018
  25. Yang, T. (2013), "Healing of carbon fibre-epoxy composite T-joints using mendable polymer fibre stitching", Compos. Part B, 45, 1499-1507. https://doi.org/10.1016/j.compositesb.2012.08.022
  26. Yoshimura, A. (2008), "Improvement of out-of-plane impact damage resistance of CFRP due to through-thethickness stitching", Adv. Compos. Mater., 18(2), 121-134. https://doi.org/10.1163/156855109X428727