Microscale Tests of Cement Paste Performed with FIB and Nanoindentation

Abstract:

This study deals with experimental determination of tensile properties of cement paste hydration products at micro-scale. Cantilever micro-beams with length of about 16 µm and pentagon cross section with micrometer dimensions were fabricated by focused ion beam milling on hydrated cement paste samples. Nanoindentation was used for evaluating elastic properties while tensile properties were derived from beam bending tests. Displacement controlled micro-scale tests give access to both tensile strength and estimates of fracture energy based on the load-displacement curves measured with the nanoindenter. The mean tensile strength and the fracture energy of inner hydration product were assessed as 791 MPa and 16.7 J/m², respectively. The huge difference of the micro-scale properties when compared to macroscopic values comes from the scaling properties of concrete.

• Periodical: Key Engineering Materials (Volume 760)
• Pages: 239-244
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.760.239
• Online since: January 2018
• Authors: Jiří Němeček*, Jiří Němeček
• Keywords: Cantilever Micro-Beam, Cement Paste, Focused Ion Beam, Fracture Energy, Nanoindentation, Tensile Strength

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