Improved Thermal Shock Resistance of Magnesium Aluminate Spinel Ceramics by Aluminium Titanate Additions

Christos G. Aneziris, Kirsten Moritz

Technische Universität Bergakademie Freiberg, Institute of Ceramics, Glass and Construction Materials, 09596 Freiberg/Germany

Revision 10.12.2015, 14.01.2016

Volume 8, Issue 2, Pages 67 - 73

Abstract

The capability of aluminium titanate additions to improve the thermal shock resistance of alumina-rich magnesium aluminate spinel refractories was investigated. Raw material mixtures with different maximum particle sizes of 20 μm, 1 mm, or 3 mm were used. The strength and the dynamic Young’s modulus of the spinel ceramic at room temperature were decreased by aluminium titanate, whereas the resistance to thermal shock, tested by water quenching from 950 °C, was enhanced. The dynamic Young’s modulus of the Al2TiO5-containing samples exhibited a pronounced hysteresis as a function of temperature.

Keywords

magnesium aluminate spinel, aluminum titanate, thermal shock resistance, dynamic Young’s modulus

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