High-Temperature Mechanical Characterisation of In-Situ Forming Spinel-Alumina Castables Using Magnesia or Magnesite as Raw Material
1 BCRC – Belgian Ceramic Research Centre, (Member of EMR), 7000 Mons/Belgium
2 FGF Forschungsgemeinschaft Feuerfest e. V., 56203 Höhr-Grenzhausen/Germany
3 Hochschule Koblenz, 56203 Höhr-Grenzhausen/Germany
Revision 30.07.2018, 25.10.2018
Volume 11, Issue 1, Pages 82 - 87
Abstract
In this work, four alumina-magnesia, cement-bonded castables were tested at high temperature. Strength was determined by bending test at temperature ranging from room temperature to 1550 °C. As a reference, a high alumina castable was also investigated. The effect of several parameters: composition, addition of magnesia or magnesite (carbonate) and microsilica addition were investigated. Strength-displacement curves were also recorded during the tests. Microscopic observation and XR diffraction were also introduced to support the discussion and conclusions of the work. Results demonstrate the effect of some parameters on high temperature mechanical behaviour: sintering, phase transformations and liquid phase appearance vs. temperature.
Keywords
temperature, strength, castable, spinel, alumina
References
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