Influence of modified carbonate calcium nanoparticles on the mechanical properties of carbon fiber/epoxy composites

Multiscale composites have been investigated by the addition of silanized carbonate calcium (CaCO3) as a secondary reinforcement into the matrix of carbon fiber/epoxy composites. The chemical modification of the CaCO3 nanoparticles was confirmed by Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Mechanical properties of the specimens were investigated by means of tensile, flexural, and compressive measurements to study the effect of treated CaCO3 loading (0.5, 1, 3 and 5 wt.%) on their mechanical behavior. Experimental results showed that the tensile, flexural and compressive strengths of the specimen filled with 3 wt.% treated CaCO3 composite enhanced by 14%, 36%, and 30% respectively, compared with those of neat one. The highest improvements in the mechanical moduli were observed in the multiscale composite filled with 5 wt.% treated CaCO3. Also, the fracture surface of the specimens was further analyzed in detail.