Papers by Keyword: Quantitative Phase Analysis QPA

Abstract: Quantitative X-Ray diffraction (QXRD) combined with the Rietveld refinement method allows direct determination of crystalline phase content of cement and its hydrates. However, relatively precise results need the correction of proper internal standards and the use of matched peak profile functions with masterly refinement strategies. The aim of this paper is to research and discuss effects of these factors on the quantitative phase analysis results. For this purpose, different internal standards and peak profile functions with corresponding refinement strategies were attempted in experiments and refinements. The results indicate that Al₂O₃ as internal standard is more suitable for cement and its hydrates than ZnO, and the better peak profile function is CW function 2 rather than function 3 in GSAS.

Abstract: On the basis of data gathered in connection with a certification project, problems were investigated that impair the accuracy of quantitative phase analyses (QPA) using the Rietveld method. Some mechanisms were elucidated by which insufficient counting statistics of the diffraction data or inappropriate data handling and refinement strategy influence the QPA results.