Effects of ageing on mechanical properties of stiffened syntactic foam core sandwich composites for marine applications

Sandwich composites and syntactic foams independently have been used in many engineering applications. However, there has been minimal effort towards taking advantage of the weight saving ability of syntactic foams in the cores of sandwich composites, especially with respect to the impact response of structures. To that end, the goal of this study is to investigate the mechanical response and damage mechanisms associated with syntactic foam core sandwich composites subjected to dynamic impact loading. In particular, this study investigates the influence of varying cenosphere volume fraction in syntactic foam core sandwich composites subjected to varying dynamic impact loading and further elucidates the extent and diversity of corresponding damage mechanisms. The syntactic foam cores are first fabricated using epoxy resin as the matrix and cenospheres as the reinforcement with four cenosphere volume fractions of 0% (pure epoxy), 20%, 40%, and 60%. The sandwich composite panels are then manufactured using the vacuum assisted resin transfer molding process with carbon fiber/vinyl ester facesheets. Dynamic impact tests are performed on the sandwich composite specimens at two energy levels of 80 J and 160 J, upon which the data are post-processed to gain a quantitative understanding of the impact response and damage mechanisms incurred by the specimens. A qualitative understanding is obtained through micro-computed tomography scanning of the impacted specimens. In addition, a finite element model is developed to investigate the causes for different damage mechanisms observed in specimens with different volume fractions.

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Compressive Behaviour of Low Density Polymeric Syntactic Foams

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.799-800.135 ◽

2015 ◽

Vol 799-800 ◽

pp. 135-139

Author(s):

Zulzamri Salleh ◽

Md Mainul Islam ◽

Jayantha Ananda Epaarachchi

Keyword(s):

Mechanical Properties ◽

Syntactic Foam ◽

Syntactic Foams ◽

Compression Tests ◽

Weight Percentage ◽

Polymer Resin ◽

Compression Properties ◽

Materials Used ◽

Marine Applications ◽

Good Compression

The combinations of polymer resin and glass microballoon are the main materials used to produce syntactic foams. Syntactic foam is a lightweight material that has good mechanical properties and is commonly used as a component for structural materials in civil construction, aerospace and marine applications. Hence, it should have suitable mechanical properties, particularly good compression behaviour. In the present study, the results obtained from compression tests are compressive strength, elastic modulus and specific compression that decrease when increasing of glass microballoon contents (2.0 wt.%, 4.0 wt.%, 6.0 wt.%, 8.0 wt.% and 10.0 wt.%) and also neat resin. The highest strength value for compression testing is owned by 2.0 wt.% which is 88.9 MPa, while the lowest strength is 43 MPa that belongs to 10.0 wt.% of glass microballoon. This shows that the density and weight percentage of glass microballoon in these syntactic foams affect compression properties. Therefore, a further study should be conducted, which includes the effect of compressive failure mechanism.

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Characterization of Flexural Properties of Syntactic Foam Core Sandwich Composites and Effect of Density Variation

Journal of Composite Materials ◽

10.1177/0021998305052037 ◽

2005 ◽

Vol 39 (24) ◽

pp. 2197-2212 ◽

Cited By ~ 52

Author(s):

Nikhil Gupta ◽

Eyassu Woldesenbet

Keyword(s):

Syntactic Foam ◽

Density Variation ◽

Flexural Properties ◽

Foam Core ◽

Sandwich Composites

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