Effect of Molarity and Temperature of Alkaline Activator Solution on the Rheological Properties and Structure Formation of Alkali-Activated Refractory Materials

The effect of the molarity (from 3.64 to 1.74 M) of an alkaline activator solution (AAS) and temperature (from 10 to 20°C) of a mixture of alkali-activated materials (AAM) based on chamotte and metakaolin on the rheological properties, structure development on solidification, and strength of samples after firing at temperatures 800 and 1000°C was studied. It was determined that reducing the molarity of AAS and raising the temperature reduces the viscosity of the AAM mixture. Increasing the molarity of AAS and the temperature of the mixture accelerates structure formation and increases the strength of samples from 8.8 to 22 MPa on solidification and from 6.8 to 20 MPa after firing at temperature 1000°C. The density of the samples after firing increases from 1270 to 1510 kg/m3, and water absorption decreases from 15.4 to 13.4%.

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Correspondence to I. Pundiene.

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Translated from Steklo i Keramika, No. 2, pp. 18 – 23, February, 2020.

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Pundiene, I., Pranckeviciene, I. & Zhu, C. Effect of Molarity and Temperature of Alkaline Activator Solution on the Rheological Properties and Structure Formation of Alkali-Activated Refractory Materials. Glass Ceram 77, 51–56 (2020). https://doi.org/10.1007/s10717-020-00236-1

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Key words

  • alkali-activated materials
  • viscosity
  • structure development
  • strength in compression