Preparation and application of ZrC-coated flake graphite for Al2O3-C refractories

In the study, ZrC-coated flake graphite was prepared by molten salt synthesis and added to the Al2O3-C refractory. The effects of the molar ratio of Zr/C and the graphite particle size on ZrC-coated flake graphite were investigated. Moreover, the oxidation resistance of the prepared ZrC-coated flake graphite was evaluated. Finally, the effect of ZrC-coated flake graphite on the properties of the Al2O3-C refractory was investigated. The results indicated that Zr and C reacted completely as the Zr/C molar ratio decreased. Furthermore, with a decrease in the graphite particle size, the reaction between Zr and C was more complete and the size of the peeling layer decreased. When compared with natural flake graphite, ZrC-coated flake graphite exhibited better oxidation resistance. The Al2O3-C refractory with 3 wt% ZrC-coated flake graphite exhibited optimal oxidation resistance and that with 1 wt% ZrC-coated flake graphite exhibited optimal slag corrosion resistance ability. (C) 2019 Elsevier B.V. All rights reserved.