关键词: 炼铁高炉, 风口, 碳化硅, 抗碱侵蚀性能

Abstract: SiC assembled large blocks for blast furnace tuyere were prepared using silicon carbide particles (3-1 and 1-0.088 mm) and fine powder (<0.088 mm),silicon powder (<0.088 mm),industrial carbon black (N990),microsilica,and ρ-Al₂O₃,etc.as raw materials.The new blocks were compared with silicon nitride bonded silicon carbide brick,self-bonded silicon carbide brick and imported self-bonded silicon carbide brick to analyze and evaluate their service performance.The results show that:(1)in the 0-100 mm zone,the new SiC large block manly consists of composites of β-SiC and one or more nitrides such as O’-SiAlON,β-SiAlON,α-Si₃N₄,and Si₂N₂O,the bulk density is 2.68-2.70 g·cm^-3,the apparent porosity is 14%-15%,and the material structure is uniform;(2)in the 0-100 mm zone,β-SiC nano-whiskers intercalate with nitrides;with the depth increasing,the flocculent β-SiC nano-whiskers increase,while the nitrides decrease;when the depth reaches 150 mm or more,the main bonding phases are β-SiC and mullite;(3)compared with the reference products,the new SiC block has a good basic performance,and after alkali corrosion,the mass change rate is -0.1%,which is obviously superior to the imported self-bonded silicon carbide and the homemade silicon nitride bonded silicon carbide materials.

Key words: blast furnace for iron-making, tuyere, silicon carbide, alkali corrosion resistance