Title: Analysis and Fabrication of Thick Co-Cured Composite Structures

Authors: Zeaid Hasan, Jessica Rader, Delphine Turpin, Alec Olson, Ryan St Onge, and Jon Amback

DOI: 10.33599/nasampe/s.19.1580

Abstract: Over the past decade advances in the design, materials, and manufacturing of thermoset composite materials have expanded rapidly. Nonetheless, aerospace structures have not yet adopted many of these technologies. This can be attributed to the risk averse nature of the engineering community and associated regulatory agencies in this field.

One of the technologies that has recently gained more traction is the use of unitized co-cure structures. Driving this change is the potential for reducing part count, touch time and labor costs. Most of the work to date focuses on thinner structures (~0.15 inch in thickness) resulting in a lack of work on much thicker parts representing wing-like structures.

This study sheds light on a recent large scale wing skin demonstrator built to understand the behavior of a thick co-cure stiffened wing skin. Details regarding the tooling concept, lamination and process development as well as post cure behavior will be discussed.

Keywords: co-cure, materials, composites, aerospace, analysis, cure cycle

References: [1] Kumara, M., et al. 2012, “Fractographic Analysis of Tensile Failures of Aerospace Grade Composites” Materials Research. 2012; 15(6): 990-997 [2] Schmid, T., et al, 2015, “Bonding of CFRP primary aerospace structures – discussion of the certification boundary conditions and related technology fields addressing the needs for development” Composite Interfaces 22(8):795-808 [3] Rao, S., et al, 2018, “Carbon Composites are Becoming Competitive and Cost Effective” Infosys white Paper [4] Allen, G., Belisario, D., 2004, “Co-cured composite structures and method of making them” US Patent US6743504B1 [5] Simpson, C. et al, 2010, “Single piece co-cure composite wing” US Patent Application US20060249626A1 [6] Stephens, J. et al 2012, “Method and Apparatus for Co-Curing Composite Skins and Stiffeners in an Autoclave” US Patent Application US20140096903A1 [7] Biornstad, R., 2004, “Composite barrel sections for aircraft fuselages and other structures, and methods and systems for manufacturing such barrel sections” US Patent US7527222B2 [8] Humfeld, K., Nelson, K., 2015, “Co-curing process for the joining of composite structures” US Patent US9731453B2 [9] Hasan, Z., et al, 2018, “Unitized Composite Structure Manufacturing System” US Patent Application [10] Abliz, D., et al, 2013, “Mixed-mode fracture toughness of co-cured and secondary bonded composite joints” Polymers and Polymer Composites 21(6):341-348 [11] Gaddikeri, K., Rao, M., 2002, “Co-curing Techniques for Integrally Stiffened Shells” Conference Paper · January 2002 [12] Huang, C., 2003, “Study on co-cured composite panels with blade-shaped stiffeners” Composites Part A Applied Science and Manufacturing 34(5):403-410 [13] Kim, G., et al, “Manufacture and performance evaluation of the composite hat-stiffened panel” Composite Structures Volume 92, Issue 9, August 2010, Pages 2276-2284 [14] Centea, T., et al, 2015, “A review of out-of-autoclave prepregs – Material properties, process phenomena, and manufacturing considerations” Composites Part A: Applied Science and Manufacturing Volume 70, March 2015, Pages 132-154 [15] Geissberger, R., et al, 2017, “Rheological modelling of thermoset composite processing” Composites Part B: Engineering Volume 124, 1 September 2017, Pages 182-189 [16] Davidson, P., Waas, A., 2017, “The effects of defects on the compressive response of thick carbon composites: An experimental and computational study” Composite Structures Volume 176, 15 September 2017, Pages 582-596 [17] Hasan, Z., 2014, “An investigation into the performance of composite hat stringers incorporating nanocomposites using a multiscale framework” Journal of Reinforced Plastics and Composites, Vol 33, Issue 15. [18] Hasan, Z., Chattopadhyay, A., 2013, “Thermo-Mechanical Analysis of Structural Elements Incorporating Nanocomposites” ASME 2013 International Mechanical Engineering Congress and Exposition Volume 9: Mechanics of Solids, Structures and Fluids [19] Hasan, Z., et al, 2014, “Multiscale approach to analysis of composite joints incorporating nanocomposites” Journal of Aircraft 52 (1), 204-215 [20] Hasan, Z., et al, 2019, “Design, Analysis and Fabrication of Thick Co-cured Wing Structures” Composites Part B, In Review. [21] https://www.plm.automation.siemens.com/global/en/products/nx/fibersim.html [22] Price, T., 1997, “Handbook: Manufacturing Advanced Composite Components for Airframes” U.S. Department of Transportation, FAA. [23] https://www.convergent.ca/products/raven-simulation-software [24] Nelson RH, Cairns DS (1989) Prediction of dimensional changes in composite laminates during cure. 34th International SAMPE symposium and exhibition, vol 34, pp 2397–2410 [25] Johnston, A., 1997, “An Integrated Model of the Development of Process-Induced Deformation in Autoclave Processing of Composite Structures” Thesis [26] Zobeiry, N., et al. 2003, “Efficient Modelling Techniques for Predicting Processing Residual” [27] Padovec, Z., 2012, “Springback analysis of thermoplastic composite plates” Applied and Computational Mechanics 6 (2012) 25–34 [28] Bogetti TA, Gillespie JW Jr (1992) Process-induced stress and deformation in thick-section thermoset composite laminates. J Compos Mater 26(5):626–660 [29] https://www.convergent.ca/products/compro-simulation-software [30] Sadd, M, 2005, “Elasticity, Theory, Application and Numerics” Elsevier Butterworth Heinemann [31] http://www.roymech.co.uk/Useful_Tables/Beams/Curved_beams.html

Conference: SAMPE 2019 - Charlotte, NC

Publication Date: 2019/05/20

SKU: TP19--1580

Pages: 21

Price: FREE