Structure and mechanical properties of composites with diamond particles dispersed into modified epoxy matrix

The structure and properties of epoxy matrix composites embedded with up to 30 wt.% of diamond particles were investigated by means of thermal analysis, mechanical testing and scanning electron microscopy, SEM. In particular, the effect of matrix deformability on the composite performance was evaluated by changing the epoxy monomer to hardener ratio. The results showed that the dynamic mechanical parameters improved with the amount of diamond particles and are markedly affected by modifications in the epoxy matrix. By contrast, the quasi-static mechanical properties decrease with the amount of diamond, which could be explained by SEM analysis. This behavior was attributed to the development of a weak diamond/epoxy interface and corroborated by the analysis of the fracture surfaces as well as the variation of the dynamic mechanical parameters for the investigated conditions.