| Authors |
Gonzalez-Corrochano, B; Cobo-Ceacero, CJ; Moreno-Maroto, JM; Uceda-Rodríguez, M; López-García, AB; Cotes-Palomino, T; Martínez-García, C; Tyrer, M; Alonso-Azcárate, J |
| Abstract |
A selection of fifty-one artificial aggregates, manufactured with different proportions of kaolinite, an iron phase (Fe0, Fe2O3, Fe3O4 or FeS2), cork powder and sodium carbonate in three previous works, have been studied mineralogically using the quantitative Rietveld XRD method. Comparisons between the mineral percentage in the raw materials and the phase percentage in the aggregate have been carried out. Additionally, independence contrast tests have been conducted to determine if significant relationships exist between the raw material mineralogical composition and the aggregate phase composition. Based on these statistical results, the mineralogical evolution, the possible reactions that may have taken place and the type of atmosphere required for them have been presented. Mullite, metallic iron, cristobalite, hematite, magnetite, hercynite, fayalite, clinopyroxenes, troilite, nepheline and amorphous material were new phases produced in the aggregates. The presence and/or percentage of the majority of them were greatly influenced by the added iron phase and by the type of atmosphere in the aggregates. In the latter, cork powder and/or sodium carbonate addition played an important role since their thermal decomposition could give rise to different conditions (oxidizing, reducing or both) depending on whether it is the external or internal zone of the aggregates |
