CUESTA, ANAICHIKAWA, RODRIGO U.LONDONO-ZULUAGA, DIANADE LA TORRE, ANGELES G.SANTACRUZ, ISABELTURRILLAS, XAVIERARANDA, MIGUEL A.G.2017-10-052017-10-052017CUESTA, ANA; ICHIKAWA, RODRIGO U.; LONDONO-ZULUAGA, DIANA; DE LA TORRE, ANGELES G.; SANTACRUZ, ISABEL; TURRILLAS, XAVIER; ARANDA, MIGUEL A.G. Aluminum hydroxide gel characterization within a calcium aluminate cement paste by combined Pair Distribution Function and Rietveld analyses. <b>Cement and Concrete Research</b>, v. 96, p. 1-12, 2017. DOI: <a href="https://dx.doi.org/10.1016/j.cemconres.2017.02.025">10.1016/j.cemconres.2017.02.025</a>. Disponível em: http://repositorio.ipen.br/handle/123456789/27836.0008-8846http://repositorio.ipen.br/handle/123456789/27836There are many commercially importantmultiphasematerialswhich contain amorphous phases, such as cement pastes, porcelains, glass-ceramics or pharmaceutical compounds. However, the analysis of amorphous phase(s) within cement matrices that contain high amounts of crystalline phase(s) is a challenge. Here, we report measurements of total scattering data quantitatively analyzed by Pair Distribution Function (PDF) minimization and Rietveld methodology to determine phase compositions including both amorphous and nanocrystalline phase contents in cement-related samples. Furthermore, laboratory techniques were used to complement the sample characterization. In addition to five reference materials, the main phase of calcium aluminate cements, CaAl2O4 hydrated at 50 °C to yield crystalline hydrogarnet, Ca3Al2(OH)12, (43wt%) and nanocrystalline aluminum hydroxide gel, Al(OH)3·0.1H2O (50wt%)was also investigated. The PDF analyses revealed that the hydroxide gel has a gibbsite local structurewith an average particle size close to 5 nm. PDF and Rietveld quantitative phase analysis results fully agree.1-12openAccessaluminiumhydroxidesgelsx-ray diffractioncalciumaluminatescementsgarnetsamorphous stateArtigo de periódico9610.1016/j.cemconres.2017.02.02590.81