The Formation of Stratlingite in Calcium Aluminate Containing Castable Systems
1 Department of Earth and Planetary, Systems Science, Faculty of Science, Hiroshima University, Hiroshima 739-8526/Japan
2 Kerneos do Brasil, 24722-030 Sao Gonçalo, Rio de Janeiro/Brazil
3 Kerneos Japan, Tokyo 103-0007/Japan
4 Kerneos France, 92521 Neuilly sur Seine Cedex/France
Revision
Volume 5, Issue 3, Pages 89-96
Abstract
The hydration mechanism of low cement castables has been long investigated but only a limited number of studies focused on specific hydrates are available. This paper will investigate a formation of stratlingite (C2ASH8), which is believed to prevent a conversion of metastable hydrates to the stable C3AH6 in high alumina cement-silica fume systems. The stratlingite formation at 21 °C and 35 °C was confirmed by XRD. Its early formation at higher curing temperature is accelerated by the addition of sodium tripolyphosphate as evidenced by XRD.
Keywords
calcium aluminate cement, stratlingite, deflocculant, silica fume, sodium tripolyphosphate, hydrates, EPMA, SEM
References
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