Analysis of mechanical characteristics of fly ash cenospheres reinforced epoxy composites

Abstract

Fly ash cenospheres (FACs) as a recycling material of industrial waste has become a competitor for other inorganic particle fillers. Epoxy resin (EP) composites reinforced with different content of FACs as well as different size grading ratio were prepared. The surface modification of FACs particles was conducted before incorporating into EP matrix. The impact and flexural strengths and the flexural modulus were investigated, and the fracture surfaces of the testing samples were analyzed using SEM. Results showed that FACs had an obvious effect on the mechanical characteristics of the FACs/EP composites. With increasing weight fraction of FACs, the impact and flexural strengths and the flexural modulus of EP composite samples increased, and reached the highest values when the weight fraction of FACs reached 15 wt%. The mechanical characteristics of the FACs/EP composites however deteriorated with further increasing of FACs content. For the EP composites reinforced with different size grading ratio of FACs, the larger proportion of small FACs particles, the better mechanical properties of the EP composites. The results were analyzed from the aspect of the plastic deformation, new surface formation and fracture absorption energy. The synergistic effect of the size grading ratio of FACs was not obvious, which would be further investigated.

Keywords

fly ash cenospheres / epoxy resin / mechanical characteristics / surface modification

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