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Environmental Scanning Electron Microscopy as a Tool to Study Shrinkage Microcracks in Cement-Based Materials

Published online by Cambridge University Press:  10 February 2011

J. Bisschop  and
J.G.M. Van Mier
J. Bisschop
Affiliation:
Faculty of Civil Engineering and Geo-Sciences, Delft University of Technology, P.O. Box 5048, 2600 GA Delft, The Netherlands, J.Bisschop@ct.tudelft.nl
J.G.M. Van Mier
Affiliation:
Faculty of Civil Engineering and Geo-Sciences, Delft University of Technology, P.O. Box 5048, 2600 GA Delft, The Netherlands
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Abstract

In this paper a method is described to observe shrinkage microcracks on ‘wet’ specimen cross-sections of cement-based materials with Environmental Scanning Electron Microscopy (ESEM). A sample cooling device which can be used in the ESEM chamber was built to control the relative humidity above a microscope sample. The accuracy of measuring relative humidity is determined to be 5% at a sample temperature of 3°C. A microscope sample preparation method and a pump-down sequence of the ESEM-chamber, both without any drying of the sample, are described. Preliminary results show that in the studied mortar the visibility of shrinkage microcracks on a ‘wet’ specimen cross-section is low due to closure of microcracks by swelling of the cement paste.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 589 , 1999 , 141
Copyright
Copyright © Materials Research Society 2001

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