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ASTM guide covers scanning electron microscopy for hardened concrete


Sources: ASTM International, West Conshohocken, Pa.; CP staff
Absence of standardized procedures for a method used since the 1960s to examine concrete specimens’ mix constituents, water/cement ratio and related quality control attributes has led to ASTM C1723–10 Standard Guide for Examination of Hardened Concrete Using Scanning Electron Microscopy. The new guide assists petrographers in performing scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), and maximize the techniques’ utility in examining concrete, mortar and stucco specimens.

Encompassing a general introduction to SEM/EDX analytical techniques, ASTM C-1723-10 is geared to concrete engineers and scientists familiar with, but not expert in, related equipment and technology application. The SEM provides low to high magnification of concrete fragments, polished surfaces, or powders; images, or micrographs, can provide information indicating specimen’s compositional or topographical variations. The EDX system can be used to qualitatively or quantitatively determine the elemental composition of very small volumes, perhaps 1–10 microns, intersecting the specimen’s surface. Measured compositional determinations can be correlated with specific features observed in the SEM image. Copies of the standard can be ordered by clicking here. (http://www.astm.org/Standards/C1723.htm?A).