The morphology and composition of an immature C3S paste

doi:10.1016/0008-8846(77)90055-2

Cement and Concrete Research

Volume 7, Issue 6, November 1977, Pages 711-718

https://doi.org/10.1016/0008-8846(77)90055-2 Get rights and content

Abstract

The morphology of a one month old hydrated C₃S paste has been studied using the scanning electron microscope (SEM) and preferential etching techniques. The C/S ratios of the calcium silicate hydrates (CSH) have been determined using the SEM with an energy dispersive spectrometer. The hydrate rims covering the partially hydrated C₃S grains were found to consist of two layers; an outer porous product with an acicular morphology having a C/S ratio of 1.6 ± 0.1 and an inner product with a C/S ratio of 1.90 ± 0.05.

A region of increased C/S ratio in the C₃S core at the C₃S-CSH interface is attributed to a depletion of SiO₂ resulting from the diffusion of Si⁴⁺ ions into the hydrate.

Résumé

La morphologie d'une pâte de C₃S qui hydraté pour un mois, a été étudieé avec un microscope electronique a balayage (SEM) et les techniques d'attaque par acide. Les C/S des silicates de calcium hydrate (CSH) ont été determinés avec le SEM équipé d'un spectromètre X dispersif en énergie. Les jautes des hydrates qui couvrait les grains de C₃S consistait des deux poseurs; un produit exterieur avec une morphologie fibreux, C/S = 1.6 ± 0.1, et un produit intérieur avec un C/S = 1.90 ± 0.05.

Dans le grain de C₃S y est un region à la frontière de C₃S - CSH qui a un C/S > 3. C'est attribué a ùn épuisement de SiO₂ qui résulte du diffusion des ions de Si⁴⁺ dans le hydrate.

References (5)

S. Diamond
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S. Goto et al.
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There are more references available in the full text version of this article.

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The morphology and composition of an immature C3S paste

Abstract

Résumé

Cem and Concr Res

J Am Cer Soc

The morphology and composition of an immature C₃S paste