Effect of porosity on the damping properties of modified epoxy composites filled with fly ash

The effect of porosity on the damping property of modified fly ash/epoxy composites was investigated. Results show that the loss factor of porous fly ash/epoxy composite (which has a porosity of 42%) can reach (0.73 ∼ 0.84), while that of the cracked fly ash/epoxy composite (which has a porosity of 1.4%) only reaches (0.55 ∼ 0.68), but is still higher than that of the matrix. In addition, the damping mechanisms have been qualitatively analyzed in light of the information about the microstructures, porosities and loss factors.