Impact of Melt Phase Formation on the High-Temperature Behaviour of MgO–CMA–C Refractories
1 Institute of Ceramic, Glass and Construction Materials, Technical University Bergakademie Freiberg, 09599 Freiberg/Germany
2 Imerys Aluminates, Paris/France
Revision 10.07.2019, 22.07.2019
Volume 11, Issue 4, Pages 73 - 77
Abstract
Due to their excellent thermomechanical properties and corrosion resistance against aggressive steel/slag systems, carbon bonded magnesia (MgO–C), alumina magnesia (AMC), and magnesia alumina (MAC) bricks are the dominating refr actories for the lining of the side walls and bottom of steel ladles , basic oxygen furnaces, and electric arc furnaces. In order to further improve the properties to meet the requirements for even longer service life, highly reactive spinelrich powder/aggregates (2,5 mass%, 5 mass%, and 7,5 mass%) has been introduced in the composition consisting of common MgO-C in two different qualities with 3 mass% C (after carbonisation), carbonised at 1400 °C. Melt phase formation is expected after carbonisation that could support the formation of a protective layer on the brick surface to protect the brick from slag penetration and the carbon from o xidation. Thus, the infuence of this melt phase formation on the thermomechanical properties has been studied. Besides the thermomechanical properties CCS, HMOR, apparent porosity, and median pore diameter, the phase composition after carbonisation has been analysed.
Keywords
refractories, ladle, MgO–C properties
References
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