Rietveld quantitative phase analysis with molybdenum radiation. Issue 1 (15th October 2014)

• Record Type: Journal Article
• Authors: Cuesta, Ana; Álvarez-Pinazo, Gema; García-Maté, Marta; Santacruz, Isabel; Aranda, Miguel A. G.; De la Torre, Ángeles G.; León-Reina, Laura
• Is Part Of: Powder diffraction. Volume 30:Issue 1(2015)
• Page Start: 25
• Page End: 35
• Publication Date: 2014-10-15
• Subjects: Mo and Cu radiations, -- synchrotron radiation, -- irradiated volume, -- cement, -- accuracy; Powder metallurgy -- Periodicals; Materials -- Analysis -- Periodicals; 620.1127
• DOI: 10.1017/S0885715614000785
• Languages: English
• ISSNs: 0885-7156

Abstract

Abstract : Building materials are very complex samples of worldwide importance; hence quantitative knowledge of their mineralogical composition is necessary to predict performances. Rietveld quantitative phase analysis (RQPA) allows a direct measurement of the crystalline phase contents of cements. We highlight in this paper the use of laboratory X-ray powder diffraction (LXRPD) employing high-energy radiation, molybdenum (Mo), for attaining the RQPA of cements. Firstly, we evaluate the accuracy of RQPA employing a commercial calcium sulfoaluminate clinker with gypsum. In addition to Mo Kα 1 and Mo Kα 1, 2 radiations, Cu and synchrotron patterns are also analyzed for the sake of comparison. Secondly, the assessment of the accuracy of RQPA results obtained using different radiations (synchrotron, Mo, and Cu) and geometries (reflection and transmission) is performed by analyzing two well-known commercial samples. As expected, for LXRPD data, accuracy in the RQPA results improves as the irradiated volume increases. Finally, three very complex aged hydrated cements have been analyzed using Mo K α1 -LXRPD and Synchrotron-XRPD. The main overall outcome of this work is the benefit for RQPA of using strictly monochromatic Mo Kα 1 radiation. Best laboratory results arise from Mo Kα 1 data as the effective tested volume is much increased but peak overlapping is not swelled.