Effect of Additives on Grain Growth of Titanium Carbonitride in Carbothermal Reduction Process of Titanium-Bearing Blast Furnace Slag

摘要

The effect of additives such as K_2CO_3, CaF_2 and Fe_2O_3 on the formation and grain growth of titanium carbonitride in carbothermal reduction process of titanium-bearing blast furnace slag in Panzhihua Iron and Steel Company was investigated by means of X-ray diffraction (XRD), electron probe microanalysis (EPMA) and micro-image analysis (MIAPS). The results showed that titanium components were mostly enriched in form of titanium carbonitride Ti(C, N) phase after titanium-bearing slag was treated at 1450 ℃ for holding time of 2 h in nitrogen atmosphere. All the additives could modify the liquid slag properties and accelerate effectively the grain growth of Ti(C, N). Among them, Fe_2O_3 is the most effective additive and the agglomerate of Ti(C, N) grain grew up as its amount increased. Its maximum size reached up to 23 μm when 10% Fe_2O_3 was added in titanium-bearing slag.