Comparison of Cement- and Hydratable Alumina-Bonded Alumina-Spinel Materials for Steel Ladle Purging Plugs
1 Almatis GmbH,Frankfurt/Germany
2 Almatis Qingdao/China
3 McGill University Canada/Canada
4 Chair of Ceramics, Montanuniversitaet Leoben/Austria
5 Stourbridge/Great Britain
Revision 29.04.2017, 09.05.2017
Volume 9, Issue 3, Pages 93 - 106
Abstract
This paper provides a summary of extended investigations performed on cement- and hydratable alumina bonded refractory materials for steel ladle purging plugs. The main wear factors of purging plugs are erosion due to intense stirring, corrosion by iron-oxide slag during oxygen lancing, and spalling due to thermal cycling. These were addressed in the investigation by theoretical thermodynamic evaluations using FactSage, mechanical property testing including hot modulus of rupture, and fracture behaviour testing using the wedge-splitting test. In addition, microstructural investigations were performed in order to explain differences in the material. The results provide a basis for assessment of different binder concepts especially for the purging plug application. These indicate the potential which hydratable alumina bonded materials could have in this area. Industrial and academic partners of the FIRE-network from three different continents have successfully cooperated in this study.
Keywords
Al2O3–MgO–CaO, FactSage analysis, cement bonded castable, no-cement castable, hydratable alumina, fracture behaviour, spalling, microstructure, steel ladle purging plug
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