On the characterization of syntactic foam core sandwich composites for compressive properties

Nikhil Gupta, Kishore, S. Sankaran, C. V Raman Nagar

Research output: Contribution to journalArticle

Abstract

Sandwich structures, especially those with honeycomb and grid structures as the core material, are very commonly employed in aircraft structures. There is an increasing use of closed-pore rigid syntactic foams as core materials in sandwich constructions because they possess a number of favourable properties. The syntactic foams, owing to their structure and formation, behave differently under compression compared to other traditionally used core materials. In the present study, therefore, syntactic foam core sandwich constructions are evaluated for their behaviour under compression in both edgewise and flatwise orientations. Further, the work characterizes the relative performance of two sets of sandwich materials, one containing glass-epoxy and the other, glass/carbon hybrid-epoxy skins. As non-standard geometry test specimens were involved, only a comparative evaluation was contemplated in this approach. The experiments indicate that the nature of the reinforcement fabric in the skin has a bearing on the test results in edgewise orientation. Thus, the tendency towards initiation of vertical crack in the central plane of the core material, which is a typical fracture event in this kind of material, was found to occur after a delay for the specimens containing the glass fabric in the skin. Attempts are made to establish the correlation between observations made on the test specimen visually during the course of testing and the post-compression microscopic examinations of the fracture features.

Original languageEnglish (US)
Pages (from-to)1347-1357
Number of pages11
JournalJournal of Reinforced Plastics and Composites
Volume18
Issue number14
StatePublished - 1999

Fingerprint

Syntactics
Foams
Composite materials
Skin
Glass
Sandwich structures
Reinforcement
Microscopic examination
Compaction
Carbon
Aircraft
Cracks
Geometry
Testing
Experiments

ASJC Scopus subject areas

  • Ceramics and Composites
  • Materials Chemistry
  • Polymers and Plastics

Cite this

On the characterization of syntactic foam core sandwich composites for compressive properties. / Gupta, Nikhil; Kishore; Sankaran, S.; Nagar, C. V Raman.

In: Journal of Reinforced Plastics and Composites, Vol. 18, No. 14, 1999, p. 1347-1357.

Research output: Contribution to journalArticle

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