Buckling of Sandwich Composites; Effects of Core?Skin Debonding and Core Density

Abstract

Foam-core sandwich composites have been fabricated using innovative co-injection resin infusion technique and tested under in-plane compression. The sandwich construction consisted of Klegcell foam as core materials and S2-glass/vinyl ester composites as face sheets. Tests were conducted with various foam densities and also with implanted delamination between the core and the face sheet. The intent was to investigate the effect of core density, and the effect of core-skin debonds on the overall buckling behavior of the sandwich. Analytical and finite element calculations were also performed to augment the experimental observations. It has been observed that core density has direct influence on the global buckling of the sandwich panel, while embedded delamination seem to have minimal effect on both global as well as local buckling. Detailed description of the experimental work, finite element modeling and analytical calculations are presented in this paper.

Engineering functionally graded tissue engineering scaffolds

“…The results showed that the structure with the highest core density (the closest to the face sheet density) had minimal delamination propagation. This showed that less abrupt density transition will lessen the likelihood of delamination (Mahfuz et al, 2004). Thus, it is much preferred that the scaffold functional gradients should avoid discrete gradient as much as possible.…”

Finite element buckling analysis of laminated composite sandwich panels with transversely flexible core carrying attached elastic strip

“…First the results are validated for the case of sandwich structures without attached mass. Mahfuz and Seifulislam [15] calculated the buckling load of sandwich panels with three different foam core materials experimentally. Three layers of plane weave S2 glass fibers were used in each face sheet.…”

“…The material properties and the dimensions of the panel are listed in Tables 1 and 2, respectively. Table 3 presents the results of the present model versus the experimentally calculated buckling loads in Mahfuz and Seifulislam [15].…”

“…Sandwich panel dimensions[15] Notes: Lay-up: ð0=90Þ 5 =core=ð0=90Þ 5 . Face sheets: E 11 =E 22 ¼ 19, G 12 =E 22 ¼ 0:52, G 13 =E 22 ¼ 0:52, G 23 =E 22 ¼ 0…”

Development of functionally graded biomaterial scaffolds using selective laser sintering

“…Mahfuz et al [94] performed a buckling test for three types of sandwich structures with the same face sheets but different foam core densities with embedded delamination at the interface. The results showed that the structure with the highest core density (the closest density to the face sheet density) had minimal delamination propagation.…”