1. Scope
This Guide provides information for the examination of hardened concrete using scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). Since the 1960s, SEM has been used for the examination of concrete and has proved to be an insightful tool for the microstructural analysis of concrete and its components. There are no standardized procedures for the SEM analysis of concrete. SEM supplements techniques of light microscopy, which are described in C 856, and, when applicable, C 856 should be consulted for SEM analysis. For further study, see the bibliography at the end of this Guide. This Guide is intended to facilitate the observation of cementitious and associated materials by SEM. It is critical that laboratory personnel be familiar with the operation of SEM/EDX equipment, specimen preparation procedures, and the use of appropriate procedures for this purpose. It is also critical that personnel know the significance and limitations of SEM examinations and analyses. This Guide does not discuss data interpretation. Proper data interpretation is best done by individuals knowledgeable about the significance and limitations of SEM and the materials being evaluated. 1.1.The SEM provides visual imaging from low magnifications (e.g., 15X) to high magnifications (e.g., 50,000X or greater) using methods such as backscattered electron (BSE) and secondary electron (SE) imaging techniques. Fragments, polished surfaces, or powders can be studied. See Note 1 for illustrations of using SEM to examine concrete. Note 1 An electronic document consisting of electron micrographs and EDX spectra illustrating the materials, reaction products, and phenomena discussed below is available at http://CEE.UIUC.edu/research/dlange/concretemicroscopy/. 1.2.The values stated in SI units are to be regarded as standard. 1.3.This standard does not purport to address all of the safety concerns associated with the use of electron microscopes, X-ray spectrometers, chemicals, and equipment used to prepare samples for electron microscopy. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Keywords
SEM
The title and scope are in draft form and are under development within this ASTM Committee.
Citing ASTM Standards
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