Combined effects of the graphite content and addition of aluminum in the characteristics of resin-bonded MgO-C bricks. (March 2022) - Gass, S.E.
Abstract: MgO-C bricks used in the steelmaking industry are still attracting attention despite the large amount of research developed in relation to the most pressing issues regarding their service performance. In this paper, a systematic study concerning the combined effects of critical variables such as the graphite content (varied in 8 and 12wt%) and the presence of aluminum are analyzed. The evaluated materials have controlled compositions and were manufactured in-plant with the current procedure for commercial bricks, which represents an advantage for the extrapolation of results to real working conditions. The findings concern the impact of Al on the textural characteristics of the bricks, which was more marked when more graphite was added; likewise, the metal affected the mechanical strength of the bricks (although weakly). Moreover, the higher the graphite content, the higher the brick's oxidation resistance; the antioxidant effect of aluminum was more marked when the amount of graphite was lower. Highlights: Combined effects of added Al and increasing graphite content on resin/MgO-C bricks were pointed out. Changes in the pore size distribution caused by Al were more marked for higher graphite content. The presence of Al particles causes a drop of mechanical strength for higher content of graphite. The antioxidant action of Al is more effective when the amount of graphite is lower.