The slag resistance and physical properties of magnesia-chromite, corundum-spinel and magnesia-spinel bricks, containing around 64, 4 and 80 wt percent MgO respectively, for use in VOD ladles were investigated. The quality of these bricks was mainly assessed by the experiment combining the action of slag and thermal shock on bricks and using a gas-fired rotary slag test furnace. The experimental results indicated that the corundum-spinel bricks have the least penetration/greatest corrosion values, followed by the magnesia-spinel and the magnesia-chromite bricks; and that the magnesia-spinel bricks have the greatest thermal expansion coefficient, followed by the magnesia-chromite and the corundum-spinel bricks. The magnesia-spinel bricks' good thermal shock damage resistance is believed to be due to the ZrO_2-induced microcrack structure. Field trials revealed that the corundum-spinel bricks used below the slag line after the end of a specific stainless steelmaking campaign at China Steel could be diverted for use in carbon steelmaking, although additional lining maintenance work is required to extend the life of ladle linings. One ladle after 10 heats for stainless steelmaking lasted another 74 heats for carbon steelmaking.
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