Compressive strength of Portland cement pastes and mortars containing Cu-Zn nano-ferrite

Abstract

This study is concerned with the synthesizing of Cu-Zn nano-ferrite particles in the laboratory applying simple techniques. The morphology of the synthesized nano-particles was analyzed using Transmission Electron Microscopy (TEM), and the minerals were identified using X-ray diffraction (XRD). The nano material was used to replace 1- 4 percent by weight of Portland cement in cement pastes and mortars. The microstructure and compressive strength of the composites were then evaluated. The microstructure was characterized by means of Scanning Electron Microscope (SEM) analysis and the compressive strength was evaluated at 7 and 28 days. While some specimens were tested at normal temperature, other specimens were tested after 2-hour exposure at elevated temperatures of 200^oC and 400^oC. The results showed that it was possible to synthesize nano-particles having an average size of 12 nanometers. Also, the test results revealed that the optimum content of the nano-ferrite was 1% to produce the maximum increase in the compressive strength. Adding the optimum dose of nano-particles helped to produce a denser microstructure. The paste and mortar specimens showed general tendency to lose strength after exposure to the elevated temperatures.