Analysis of flexural properties of hollow-particle filled composites

This paper studies flexural properties of vinyl ester-glass hollow-particle filled composites, which are used in marine applications. Sixteen compositions of composite materials are studied under three-point bending conditions to assess the effect of wall thickness and volume fraction of hollow inclusions. The results show that the flexural modulus of several composites is higher as compared to the neat resin. Moreover, the specific modulus of all composites is higher than the neat resin providing the possibility of appreciable weight saving in marine structures. Nevertheless, the flexural strength of the composites is lower than that of the neat resin. In addition, it is found that the flexural strength decreases as the inclusion volume fraction increases and is independent of the inclusion wall thickness. An analytical framework is presented to interpret the experimental findings and generate predictive capabilities for hollow-particle filled composites. Tractable formulas are used for computing the flexural modulus and strength from the mechanical and geometrical properties of the constituents. Analytical and experimental results are found to be in close agreement.