Open AccessInfluence of type and quantity of magnesium additive on the hardening process of alumina cement-based cement stone
Author(s) -
N. G. Chumachenko,
Vladimir V. Tyurnikov
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1015/1/012069
Subject(s) - cement , magnesite , magnesium , materials science , mullite , hardening (computing) , metallurgy , calcination , metakaolin , composite material , ceramic , chemistry , catalysis , biochemistry , layer (electronics)
The greatest effect on increasing the residual strength of cement stone based on alumina cements in the temperature range of 800-1200 °C is achieved when replacing part of the cement with thermally activated metakaolin which is associated with the formation of secondary mullite. To intensify the strengthening process of mullite formation, the influence of various magnesium additives-mineralizers has been studied. The effect of chemically pure magnesium oxide, caustic magnesite and magnesium oxide hydration product calcined at 390 - 450 °C were investigated experimentally. The content of additives in compositions based on high-purity high-alumina cement was accepted in the amount of 0.5, 1 and 1.5 %. Experiments have confirmed the positive effect of magnesium additives on the process of hardening of cement stone, both during hardening and after heat treatment. It was found that the type of magnesium additive affects the hardening process. The highest strength after hardening and drying is obtained by using caustic magnesite as a mineralizer additive in an amount of 0.5 %. Exposed to high temperature, the best results are recorded when using a chemically pure magnesium additive.