The size effect of nanoparticles on the mechanical and electrical properties of cement–Fe3O4 nanocomposite

In this study, fabrication of a nanocomposite of the ordinary Portland cement (OPC) and magnetite (Fe3O4) nanoparticles is reported. The samples of cement paste with a water/solid mass ratio (W/S) of 0.5 containing 0.2 wt.% Fe3O4 nanoparticles with four different particle sizes (20-40 nm, 80-100 nm, 250-300 nm, and ~ 5 µm) were prepared. The nanocomposite was characterized by X-ray diffraction (XRD) for phase identification, scanning electron microscopy (SEM), and its mechanical properties like compressive strength, flexural strength, and tensile strengths was evaluated. The results showed that the cement paste reinforced by magnetite nanoparticles of 20-40 nm indicated the highest compressive, flexural, and tensile strengths compared to other samples reinforced by larger particles. Addition of 0.2 wt.% Fe3O4 nanoparticles of 20-40 nm gave rise to an increase in compressive strength, flexural strength and tensile strength by 19-24, 13-18, and 8-12 %, respectively, and a decrease in electrical resistance by 21-27 %.

کلیدواژه ها:

Cement ، Magnetite nanoparticles ، Nanocomposite.