Advances in scanning electron microscopy have made possible observations of wet specimens at high magnifications. New techniques using the environmental scanning electron microscope allow the study of cement-based materials at critical early stages of the hydration process with no disturbance to the material and its developing microstructure. The microscope provides specimen chamber pressures sufficiently high for water to remain on surfaces and in the pore structure. A cooling stage facilities observation of wet specimens by lowering the temperature of the specimen and therefore the partial pressure necessary for liquid water. A microinjector mechanism permits water to be added during imaging of the specimen. Dissolution and precipitation processes in cement paste are observed uninterrupted and recorded on videotape. The advanced capabilities have contributed new insight into microstructural development in cement paste.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics