Rietveld Quantitative Phase Analyses Of Srm 2686A: A Standard Portland Clinker

SRM 2686a is a NIST reference Portland clinker with a reported mineralogical analysis from powder<br> diffraction and electron microscopy. Furthermore, this sample is used in ASTM C1365 test method for<br> Rietveld quantitative phase analysis validation procedure. Here, we have analysed SRM 2686a by<br> using three state-of-the-art powder diffraction configurations: i) strictly monochromatic CuKα1<br> radiation in flat reflection geometry; ii) strictly monochromatic MoKα1 radiation in flat transmission<br> geometry; and iii) synchrotron radiation in rotating capillary transmission geometry. The powder<br> patterns were analysed by Rietveld methodology with the best available protocols. The results indicate<br> that the reported NIST analysis overestimate belite content which explains problems found for<br> implementing ASTM C1365 in some cement manufacturing plants. Furthermore, the three patterns are<br> deposited as open data access at Zenodo, so interested laboratories can analyse these data to verify their<br> protocols.