Flexural Behaviour of Fibre‐Reinforced Syntactic Foams

Abstract

Summary: Syntactic foams containing 0.9, 1.76, 2.54, 3.54 and 4.5 vol.‐% of E‐glass fibres in the form of chopped strands were processed and subjected to three‐point bending tests. The results showed that introduction of chopped strand fibres into the syntactic foam system increased the flexural strength. The values increased with the amount of fibres in the foam system except for the one containing 3.5 vol.‐% of fibres, which showed a lower value than other fibre‐reinforced systems, thereby deviating from the trend. This exception was attributed to the difference in processing route adopted for this particular fibre‐bearing foam. However, in general, the incorporation of chopped strand fibres improved the flexural behaviour of the syntactic foam system without much variation in density, thus making reinforced syntactic foams to act as better and improved core materials for sandwich applications.Fibre‐debonding and protuberance, and river pattern in a failed sample.magnified imageFibre‐debonding and protuberance, and river pattern in a failed sample.

Analysis of a functionally graded particulate composite under flexural loading conditions

“…Studies on three-point bend tests have been conducted in either flexural [14,23] or short beam shear test configurations [15][16][17]. In addition, fiber reinforced syntactic foams [24][25][26] and syntactic foam core sandwich composites have also been studied for bending properties [27]. Several studies on fracture toughness of syntactic foams have tested pre-cracked specimens under three-point bend conditions [28][29][30][31].…”

Flexural Properties of Syntactic foam Reinforced by Warp Knitted Spacer Fabric

“…Presently, embedding short fibres in syntactic foams is a viable means for enhancing the flexural properties of syntactic foams. Many researchers reported that the incorporation of chopped strand glass fibres or carbon fibres could improve the flexural properties of syntactic foams [1,[7][8][9]. However, this method has some limitations; short fibres are hard to uniform disperse and may cluster and bunch in the matrix.…”

“…Due to the clustering and bunching, the fibres are not completely wet by the matrix hence the fibres are less effective in bearing the load. And even worse, the incomplete wet fibres can make the interface region to be filled with air and eventually reduce the mechanical properties of the whole materials [7,10].…”

Syntactic Foams

“…Therefore, due to this clustering, the fibers were not completely wet by the resin matrix; hence the fibers were less effective in bearing the load transferred from the matrix. Thus, the latter method was found to be more effective, as evident from the lower void content and good mechanical properties [123,124]. The compressive modulus also increased with the content of fibers in the system, except for the one containing 3.54% of fibers, which showed a lower value than other fiber-reinforced systems [125].…”