INVESTIGATIONS OF CARBON BRICKS FOR THE B LAST-FURNACE HEARTH LINING UNDER THE EFFECT OF HOT METAL

Various carbon brick grades have been investigated in terms of their r esistance to dissolution and infiltration of liquid hot metal. The Ins titute of Ferrous Metallurgy of the RWTH Aachen is equipped with two s uitable testing installations, which make it possible to analyze separ ately each individual wear mechanism. The investigation of the resista nce to infiltration has shown that, subject to an appropriate raw mate rial selection and the addition of Si(met), less hot metal will penetr ate these bricks. A theoretical analysis of the infiltration process i n a porous carbon body has revealed that a reduction of the pores with a diameter larger than 1 mum is sufficient to achieve an efficient pr otection against hot metal infiltrations. The experimental results sho w, furthermore, that carbon brick grades on anthracite basis feature a higher resistance to dissolution by hot metal than those which contai n graphite in their raw material mixture. The addition of Al2O3 to the bonding matrix leads, however, in both grades to a considerable impro vement of the resistance to dissolution by hot metal.