Influence of selected metal oxides in micro and nanoscale on the mechanical and physical properties of the cement mortars

摘要

The paper describes the results of the influence of three metal oxides' particles: microparticles of Fe2O3 (d ≤ 5 μm) and Fe3O4 (d ≤ 5 μm) as well as nanoparticles of NiO (d ≤ 50nm) on the cement matrix properties. Four different contents of each metal oxides' particles were applied: 0.5, 1, 2 and 3 wt.%. The studies regarding different physical and chemical parameters of cement matrix specimens such as compressive strength, water absorption, microscopic and structural properties have been carried out and the results of these studies are presented and discussed. It was shown that the micro and nanoparticles in the amounts of 2÷3 wt.% can influence the cement hydration process and thereby enhance the compressive strength of mortar. The higher enhancement was obtained during the first seven days of hardening due to so called filling effect. In the following stage of hydration the strengthening effect diminished. This phenomena was convergent with the XRD analysis, which proved that the micro-and nano-particles did not react with the cement paste components.