Premium
Cryo‐FIB‐nanotomography for quantitative analysis of particle structures in cement suspensions
Author(s) -
HOLZER L.,
GASSER PH.,
KAECH A.,
WEGMANN M.,
ZINGG A.,
WEPF R.,
MUENCH B.
Publication year - 2007
Publication title -
journal of microscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.569
H-Index - 111
eISSN - 1365-2818
pISSN - 0022-2720
DOI - 10.1111/j.1365-2818.2007.01804.x
Subject(s) - materials science , agglomerate , dissolution , ettringite , precipitation , particle (ecology) , cement , particle size distribution , particle size , chemical engineering , suspension (topology) , mineralogy , composite material , crystallography , chemistry , portland cement , oceanography , physics , mathematics , homotopy , meteorology , pure mathematics , engineering , geology
Summary Cryo‐FIB‐nanotomography is a novel high‐resolution 3D‐microscopy technique, which opens new possibilities for the quantitative microstructural analysis of complex suspensions. In this paper, we describe the microstructural changes associated with dissolution and precipitation processes occurring in a fresh cement paste, which has high alumina and sulphate contents. During the first 6 min, precipitation of ettringite leads to a general decrease of the particle size distribution. In the unhydrated cement paste almost no particles smaller than 500 nm are present, whereas after 6 min this size class already represents 9 vol%. The precipitation of ettringite also leads to a significant increase of the particle number density from 0.294*10 9 /mm 3 at t 0min to 20.55*10 9 /mm 3 at t 6min . Correspondingly the surface area increases from 0.75 m 2 /g at t 0min to 2.13 m 2 /g at t 6min . The small ettringite particles tend to form agglomerates, which strongly influence the rheological properties. The particular strength of cryo‐FIB‐nt is the potential to quantify particle structures in suspension and thereby also to describe higher‐order topological features such as the particle–particle interfaces, which is important for the study of agglomeration processes.