Iron speciation in blast furnace slag cements

Slag-containing pastes and concretes were analysed by element-specific synchrotron-based techniques to determine the speciation of iron on crushed materials through spatially resolved micro-spectroscopic studies. The investigated cement samples hydrated either in laboratory, or exposed river sea water. Metallic iron, along with minor proportions sulphide magnetite was detected laboratory sample. Iron sulphide, goethite, siliceous hydrogarnet discovered blended slag cements contact water for up 7 years. In contrast, no Fe(0) observed Instead, iron(II)-hydroxide -oxide, hematite, magnetite, hydrogarnet, goethite as well ilmenite (FeTiO3) aggregates. strong acceleration Fe oxidation long-term passivation other indicate comparable processes those occurring steel bars.