Journal of Science and Technology of Composites

Journal of Science and Technology of Composites

Three-point bending test of metal and composite sandwich panels with grid stiffened core

Document Type : Research Paper

Authors
Reza Azarafza 1
Ali Davar 1
Adib Mahmoodi2 2
1 - Department of Mechanical Engineering, Malek ashtar University of Technology, Tehran, Iran
2 Department of Mechanical Engineering, Islamic Azad University, Sanandaj Branch, Sanandaj, Iran
Abstract
Composite sandwich structures with grid stiffened core (SSGSC) are one of the new structural configurations applied in advanced industries such as aerospace, that are made of two thin face sheet layers attached to the top and bottom of a grid stiffened core. Due to the good advantages such as high specific strength, not only in aerospace but also they are used in other engineering applications, such as military industry, ship building, rail transport, oil platform etc. In the present study three composite SSGSC samples made of different material and thiknesses are fabricated with hand lay-up method using a silicon rubber mold and epoxy resin. Also, two metallic samples of the same dimensions as the copmposite ones, including a monolithic and a SSGSC samples made of aluminum are fabricated. In order to study their behavior subjected to the quasi-static transverse loads, the samples undergo three-point bending tests. Results of the practical tests on the composite samples showed that beyond the failure of the face sheets, the grid stiffened core will tolerate the load, also there are no delamination between the face sheet layers due to good curing process. It was found that changing the fibers of the face sheet from Glass to Carbon with the same thikness, improves strength-to-weight ratio of the SSGSC samples rather than increasing the thickness of the face sheet of the same material.
 
Keywords
Composite sandwich panel
grid stiffened core
Three-point bending
Loading quasi-static
Strength-weight

Subjects

[1] Huybrechts, S. and Tasi, S. W., “Analysis and Behavior of Grid Structures”, Composites Science and Technology, Vol. 56, pp. 1001-1015, 1996.
[2] Thomas, D. K., “ Fabrication and Testing of Composite Isogrid Stiffened Cylinder”, Composite Structures, Vol. 45, pp1-6, 1999.
[3] Thomas. D. K., “Fabrication and Testing of Thin Composite Isogrid Stiffened Panel”, Composite Structures, Vol. 49, pp. 21-25, 2000.
[4] Steven, M. Huybrechts, T. E. M. and Peter, M., “Manufacturing Theory for Advanced Grid Stiffened Structures”, Composites part a, Vol. 33, pp. 155-161, 2002.
[5] Prakash, J. Raju, P. Mantena, T. Gibson, F.,“Energy Absorption and Damage Evaluation of Grid Stiffened Composite Panels under Transverse Loading”, Composites part b, Vol. 37, pp. 191-199, 2006.
[6] praksh, J. Raju, P. M., “Parametric Optimization of Grid-Stiffened Composite Panels for Maximizing their Performance under Transverse Loading”, Composite Structures, Vol. 77, pp. 353-363, 2007.
[7] Hulin, F. Daining, F. and Liming, C., “Manufacturing and Testing of CFRC Sandwich Cylinder with Kagome Cores”. Composite Science and Technology, Vol. 69, pp. 2695-2700, 2009.
[8] Burgohain, M. and Velmurugan, R., “Study of Filament Wound Grid-Stiffened Composite Cylindrical Structures”. Composite Structures, Vol. 93, pp. 1031-1038, 2011.
[9] Vasiliev, V.V. A. Barynin, V. and Razin, A.F., “Anisogrid Composite Lattice Structures-Development and Aerospace Applications”. Composite Structures, Vol. 94, pp. 1117-1127, 2011.
 
Journal of Science and Technology of Composites
Volume 3, Issue 4
Winter 2017
Pages 377-388