Strength Evolution and Corrosion Resistance of a Cement-Free Al2O3-Castable Containing a Novel Hydraulic Binder Based on α-Alumina

Albrecht Wolter1, Christian Dunzen2, Oliver Splittgerber2

1 Technische Universitat Clausthal, Institut fur Nichtmetallische Werkstoffe, 38678 Clausthal-Zellerfeld/Germany
2 Nabaltec AG, 92421 Schwandorf/Germany


Volume 9, Issue 1, Pages 55 - 60


An alternative no-cement-binder system based on reactive α-alumina and magnesia (NC-Binder) for the formulation of no cement castables has recently become commercially available under the brand name NABACASTR. A first paper has been published to describe its setting mechanism, and cold processing properties of castables containing NC-Binder [1], this second paper intends to illustrate the effect on high temperature properties of castables. It describes the use of a reactive α-alumina-magnesia mix as a binder for a no cement castable and compares the properties of this castable with the properties of an ultra low cement castable. Evolution of cold compressive strength after firing at different temperatures is monitored. Slag cup tests are conducted with slags of different basicity. The results are correlated with the sintered castable’s microstructure and chemical composition. Results are verified in an induction furnace test and a model of the corrosion principle is presented.


NABACAST, no-cement castable, slag resistance


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