The Formation of Stratlingite in Calcium Aluminate Containing Castable Systems

Adriana Borovsky1, Makoto Iiyama2, Toshio Shinmei3, Chris Parr4, Makio Ohkawa5

1 Kerneos do Brasil, 24722-030 Sao Gonçalo, Rio de Janeiro/Brazil
2 Kerneos Japan, Tokyo 103-0007/Japan
3 Department of Earth and Planetary, Systems Science, Faculty of Science, Hiroshima University, Hiroshima 739-8526/Japan
4 Kerneos France, 92521 Neuilly sur Seine Cedex/France
5 Department of Earth and Planetary, Systems Science, Faculty of Science, Hiroshima University, Hiroshima 739-8526/Japan

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

[1] Lee, W.E.; Moore, R.E.: The evaluation of in situ refractories in the 20th century. J. Amer. Ceram. Soc. 81 (1998) [6] 1385–1410 [2] Daspoddar, D.; Das, S.K.; Daspoddar, P.K.: Effect of silica sol of different routes on the prop - erties of low cement castables. Bull. Mater. Sci. 26 (2003) [2] 227–231. [3] Antonovic, V.; et al.: A review of the possible applications of nanotechnology in refractory concrete. J. Civil Engin. and Management 16 (2010) [4] 594–602 [4] Cong X.; Kirkpatrick R. J.: Hydration of calcium aluminate cements: A solid-state 27Al NMR study. J. Amer. Ceram. Soc. 76 (1993) [2] 409–416 [5] Ding, J.; Fu, Y.; Beaudoin, J.J.: Stratlingite formation in high alumina cement – silica fume systems: Significance of sodium ions. Cem. Concr. Res. 25 (1995) [6] 1311–1319 [6] Ding, J.; Fu, Y.; Beaudoin, J.J.: Study of hydration mechanisms in the high alumina cement – sodium silicate system. Cem. Concr. Res. 26 (1996) [5] 799–804 [7] Fu, Y.; Ding, J.; Beaudoin, J.J.: Conversion-pre- additive for high alumina cement products. US Patent 5624489 (1997) [8] Rayment, D.L.; Majumdar, A.J.: Microanalysis of high-alumina cement clinker and hydrated HAC/slag mixtures. Cem. Concr. Res. 24 (1994) [2] 335–342 [9] Majumdar, A.J.; Singh, B.: Properties of some blended high-alumina cements. Cem. Concr. Res. 22 (1992) [6] 1101–1114 [10] Edmonds, R.N.; Majundar, A.J.: The hydration of mixtures of monocalcium aluminate and blastfurnace slag. Cem. Concr. Res. 19 (1989) [5] 779–782 [11] Bentsen, S.; Seltveit, A.; Sandberg, B.: Calcium Aluminate Cements, E.&F.N. SPON (1990) 294–319 [12] Kumar, S.; Das, S.K.; Daspoddar, P.K.: Thermo mechanical behaviour of low cement castable derived from mullite aggregates synthesized from beach sand sillimanite. Ceram. Int. 29 (2003) 671–677. [13] Sarpoolaky, H.; Ahari, K.G.; Lee, W.E.: Influence of in situ phase formation on microstructural evolution and properties of castable refrac - tories. Ceram. Int. 28 (2002) [5] 487–493 [14] Shinmei, T.; et al.: Stratlingite in hydrate of high alumina cement with silica fume. Taikabutsu 62 (2010) [2] 75–80 [15] Maeda, E.: Analysis of setting mechanism of low-cement castables (III): The acceleration of the setting by addition of Ca2+ ions. Taika butsu 62 (2010) [6] 280–290

Copyright

Göller Verlag GmbH