THE EXISTENCE OF NON-CRYSTALLINE PHASES IN ANHYDROUS PORTLAND CLINKER: AN X-RAY DIFFRACTION INVESTIGATION
An X-ray diffraction investigation
Palavras-chave:
XRD, Portland clinker, ACn, Amorphous, Rietveld refinementResumo
Portland clinker (PC) may contain an amorphous or non-crystalline (ACn) fraction most likely coming from poor phase crystallization, although there is not a consensus on that. This work assessed the presence of ACn in eight commercial PC, using CuKα1,2 and strictly monochromatic CuKα1 radiation and the external standard method. The results showed that CuKα1,2 radiation generally yielded equivalent or higher ACn contents than CuKα1 measurements. Four clinkers showed ACn contents of 8.6-12.2 wt% and 4.5-8.3 wt% respectively for CuKα1,2 and CuKα1 measurements, above the precision threshold. Thus, anhydrous Portland clinker may present an important ACn content.
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