Simulation of the forming process for curved composite sandwich panels

International Journal of Material Forming - Tập 13 - Trang 967-980 - 2019
S. Chen1, O. P. L. McGregor1, A. Endruweit1, L. T. Harper1, N. A. Warrior1
1Composites Research Group, Faculty of Engineering, University of Nottingham, Nottingham, UK

Tóm tắt

For affordable high-volume manufacture of sandwich panels with complex curvature and varying thickness, fabric skins and a core structure are simultaneously press-formed using a set of matched tools. A finite-element-based process simulation was developed, which takes into account shearing of the reinforcement skins, multi-axial deformation of the core structure, and friction at the interfaces. Meso-scale sandwich models, based on measured properties of the honeycomb cell walls, indicate that panels deform primarily in bending if out-of-plane movement of the core is unconstrained, while local through-thickness crushing of the core is more important in the presence of stronger constraints. As computational costs for meso-scale models are high, a complementary macro-scale model was developed for simulation of larger components. This is based on experimentally determined homogenised properties of the honeycomb core. The macro-scale model was employed to analyse forming of a generic component. Simulations predicted the poor localised conformity of the sandwich to the tool, as observed on a physical component. It was also predicted accurately that fibre shear angles in the skins are below the critical angle for onset of fabric wrinkling.

Tài liệu tham khảo

PUR-CSM Technology, <https://www.hennecke.com/sites/default/files/downloads/purcsm_de_en.pdf>. Accessed July 2019 Bright Lite Structures, <https://www.blstructures.com/>. Accessed July 2019 Vehicle underbody structure with lightweight PU composite, <https://www.gupta-verlag.com/news/technology/9357/vehicle-underbody-structure-with-lightweight-pu-composite>. Accessed July 2019 BMS recommends polycarbonate core for PU sandwich composites, <https://utech-polyurethane.com/news/bms-recommends-polycarbonate-core-for-pu-sandwich-composites/>. Accessed July 2019 Sloan, J., JEC World 2019 preview: Huntsmand, <https://www.compositesworld.com/products/jec-world-2019-preview-huntsman(2)>. Accessed July 2019 Automotive interior resin system, <https://www.materialstoday.com/composite-processing/products/automotive-interior-resin-system/>. Accessed July 2019 Lightweight parts interior, <https://koller-gruppe.de/en/lightweight-parts-interior/>. Accessed July 2019 Gordon Murray Design, <www.iStreamtechnology.co.uk>. Accessed June 2017 Pflug, J., EconCore, Composite Panels: Thermoplastic Solution for Demanding Applications, <http://www.econcore.com/en/products-applications/composite-panels>. Accessed June 2017 Cai Z-Y, Zhang X, Liang X-B (2018) Multi-point forming of sandwich panels with egg-box-like cores and failure behaviors in forming process: analytical models, numerical and experimental investigations. Mater Des 160:1029–1041 Chen Z, Yan N, Sam-Brew S, Smith G, Deng J (2014) Investigation of mechanical properties of sandwich panels made of paper honeycomb core and wood composite skins by experimental testing and finite element (FE) modelling methods. Eur J Wood Wood Prod 72(3):311–319 Mozafari H, Khatami S, Molatefi H (2015) Out of plane crushing and local stiffness determination of proposed foam filled sandwich panel for Korean tilting train eXpress–numerical study. Mater Des 66:400–411 Gibson LJ, Ashby MF (1999) Cellular solids: structure and properties. Cambridge university press Foo C, Chai G, Seah L (2008) A model to predict low-velocity impact response and damage in sandwich composites. Compos Sci Technol 68(6):1348–1356 Petras A, Sutcliffe M (1999) Failure mode maps for honeycomb sandwich panels. Compos Struct 44(4):237–252 Aktay L, Johnson AF, Holzapfel M (2005) Prediction of impact damage on sandwich composite panels. Comput Mater Sci 32(3–4):252–260 Chawla A, Mukherjee S, Kumar D, Nakatani T, Ueno M (2003) Prediction of crushing behaviour of honeycomb structures. Int j crashworthiness 8(3):229–235 Abrate S (1998) Impact on composite structures. Cambridge University Press, Cambridge Burton WS, Noor A (1997) Structural analysis of the adhesive bond in a honeycomb core sandwich panel. Finite Elem Anal Des 26(3):213–227 Dear J, Lee H, Brown S (2005) Impact damage processes in composite sheet and sandwich honeycomb materials. Int J Impact Eng 32(1–4):130–154 Chen S, Endruweit A, Harper L, Warrior N (2015) Inter-ply stitching optimisation of highly drapeable multi-ply preforms. Compos A: Appl Sci Manuf 71:144–156 Chen S, Harper L, Endruweit A, Warrior N (2015) Formability optimisation of fabric preforms by controlling material draw-in through in-plane constraints. Compos A: Appl Sci Manuf 76:10–19 Chen S, McGregor O, Endruweit A, Elsmore M, De Focatiis D, Harper L, Warrior N (2017) Double diaphragm forming simulation for complex composite structures. Compos A: Appl Sci Manuf 95:346–358 Chen S, McGregor O, Harper L, Endruweit A, Warrior N (2016) Defect formation during preforming of a bi-axial non-crimp fabric with a pillar stitch pattern. Compos A: Appl Sci Manuf 91:156–167 Chen S, McGregor O, Harper L, Endruweit A, Warrior N (2018) Optimisation of local in-plane constraining forces in double diaphragm forming. Compos Struct 201:570–581 Yu W-R, Harrison P, Long A (2005) Finite element forming simulation for non-crimp fabrics using a non-orthogonal constitutive equation. Compos A: Appl Sci Manuf 36(8):1079–1093 Xue P, Peng X, Cao J (2003) A non-orthogonal constitutive model for characterizing woven composites. Compos A: Appl Sci Manuf 34(2):183–193 Peng X, Cao J (2005) A continuum mechanics-based non-orthogonal constitutive model for woven composite fabrics. Compos A: Appl Sci Manuf 36(6):859–874 Khan MA, Mabrouki T, Vidal-Sallé E, Boisse P (2010) Numerical and experimental analyses of woven composite reinforcement forming using a hypoelastic behaviour. Application to the double dome benchmark. J Mater Process Technol 210(2):378–388 Boisse P, Hamila N, Helenon F, Hagege B, Cao J (2008) Different approaches for woven composite reinforcement forming simulation. Int J Mater Form 1(1):21–29 Boisse P, Aimène Y, Dogui A, Dridi S, Gatouillat S, Hamila N, Khan MA, Mabrouki T, Morestin F, Vidal-Sallé E (2010) Hypoelastic, hyperelastic, discrete and semi-discrete approaches for textile composite reinforcement forming. Int J Mater Form 3(2):1229–1240 Boisse P, Hamila N, Helenon F, Aimene Y, Mabrouki T (2007) Draping of textile composite reinforcements: continuous and discrete approaches. Adv Compos Lett 3(4):125–131 Cao J, Akkerman R, Boisse P, Chen J, Cheng H, De Graaf E, Gorczyca J, Harrison P, Hivet G, Launay J (2008) Characterization of mechanical behavior of woven fabrics: experimental methods and benchmark results. Compos A: Appl Sci Manuf 39(6):1037–1053 Harrison P, Clifford MJ, Long A (2004) Shear characterisation of viscous woven textile composites: a comparison between picture frame and bias extension experiments. Compos Sci Technol 64(10–11):1453–1465 Dassault Systèmes, Abaqus (2016) Analysis User’s Guide. 2016