Argon broad ion beam sectioning and high resolution scanning electron microscopy imaging of hydrated alite

• Published in: Cement and concrete research Vol. 150; p. 106583
• Main Authors: Kleiner, Florian, Matthes, Christian, Rößler, Christiane
• Format: Journal Article
• Language: English
• Published: Elmsford Elsevier Ltd 01.12.2021; Elsevier BV
• Subjects: Alite; Argon; Argon broad ion beam; Diameters; Electron microscopes; Electron microscopy; Hydrates; Hydration; Image analysis; Image resolution; Ion beams; Pastes; Pore size; Scanning electron microscopy; Surface preparation; Tricalcium silicate; Alite; Hydration; Argon broad ion beam; Electron microscopy; Surface preparation
• ISSN: 0008-8846; 1873-3948
• DOI: 10.1016/j.cemconres.2021.106583

Scanning electron microscopy (SEM) imaging is able to visualize micro- to nano-structures of cement and concrete. A prerequisite is that the sample preparation preserves the native structure of the specimen. In this study, argon broad ion beam (BIB) sectioning is compared to state-of-the-art sample preparation (resin embedding, polishing) for hydrated alite. Additionally, it is investigated if during BIB, sample cooling is beneficial to avoid deterioration of cement hydrates. The aim is to quantitatively measure pore size distributions in hardened alite pastes. Therefore, not only optimized sample preparation but also optimized imaging conditions are investigated. Finally, it is demonstrated that by image analysis pores down to a diameter of 5 nm in hydrated alite pastes can be quantitatively analysed. [Display omitted] •The native fibrous outer and dense inner C-S-H structure are preserved by using low energy argon broad ion beam sectioning.•Possible artefacts of the preparation and imaging of hydrated alite are shown and discussed.•An approach for a semi automated pore analysis of the obtained high resolution images is demonstrated.