QUANTITATIVE MULTI-SPECTRAL ANALYSIS OF PORTLAND CEMENT, FLY ASH AND SLAG USING SCANNING ELECTRON MICROSCOPY AND X-RAY ¿-ANALYSIS
Paul E. Stutzman
Elemental X-ray μ-analysis and scanning electron microscopy (SEM) backscattered electron imaging (BEI) are combined to develop quantitative phase maps for portland cement, fly ash, and slag. The process is facilitated with visual textural analysis of the images, and the use of general-purpose multi-spectral analysis software. The methodology is advanced from a research tool towards a standardized test through a statement of uncertainty for the results and a comparison to other measurement techniques. A standardized approach is needed because fly ashes and blended cements cannot be sufficiently characterized by a single method such as X-ray powder diffraction. Furthermore, the heterogeneous nature of the glassy phases found in fly ash result in varying chemical properties that prevent its reliable use in high volume fly ash mixtures, and a better characterization of the different glassy phases will help to formulate strategies for avoiding undesirable effects. Image processing and multi-spectral analysis facilitates quantitative measures of the different phase types, their abundance, and spatial distribution. This systematic approach developed for our Sustainable Concrete Materials program will facilitate the development of improved measurement techniques for classifying waste stream materials, and can be used to develop improved hydration kinetics models for blended systems. Ultimately, it will be a critical tool in characterizing the blended cements that will be distributed as Standard Reference Materials.
QUANTITATIVE MULTI-SPECTRAL ANALYSIS OF PORTLAND CEMENT, FLY ASH AND SLAG USING SCANNING ELECTRON MICROSCOPY AND X-RAY ¿-ANALYSIS, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=908149
(Accessed May 30, 2023)