Carbon Saturated Molten Iron Of Ti (c, N) Precipitation Of Research

In recent years, hearth of blast furnace is rapidly eroded with intensified operation of blast furnace, especially anaphase of campaign; water temperature of blast furnace hearth is often higher than usual. Blast furnace is basis of intensified operation, how to prolong BF life has become a serious problem in China's ironmaking. Titanium-bearing materials can be used for protecting blast furnace and prolonging BF life. They had been used to protecting blast furnace from 1980s, the technique has widely applied and become an important way to protect hearth of blast furnace. In the course of blast furnace smelting, when titanium-bearing materials are not enough, they can not to protect blast furnace; when titanium-bearing material are redundant, easily resulting in outrageous viscosity of molten iron, which is not good for blast furnace smelting. In order to achieve optimal effect of protecting blast furnace and economic benefit, Ti (C, N) can deposit when what is titanium content in molten iron, it is not clear, predication is often carried out by thermodynamic data, therefore, correlative theory of titanium-bearing materials for protecting blast furnace should be further investigated, scientificaalness and practicality of titanium-bearing materials for protecting blast furnace should be further perfected.Super-saturation precipitation method is adopted in this study; present condition of blast furnace is simulated to investigate sedimentation of Ti(C, N), gaining mathematic expression of titanium solubility in Fe-C_sat-Ti- (N) -j(j= Si, S, P, V, Mn etc); At the same time, influence of temperature, nitrogen pressure, Si, V, Mn on titanium solubility are studied. Results show that, at different temperatures from 1360℃～1480℃, titanium solubility increases with higher temperature; falls with higher nitrogen pressure ; falls with increasement of silicon content; increases with increasement of manganese, vanadium content.Ti(C, N)at crucible bottom is more than that at superfical coat and lateral face through energy spectroscopy of sample superficial component. When [Ti] and [C] or [N] aresupersaturation in molten iron, TiC or TiN can precipitate, including nucleation period and growth period of crystal nucleus.In ideal solid solution Ti (C, N), relationship between N_TiC and nitrogen pressure andtemperatureare as follows: during 1360℃～1480℃ range,when p_N2 is determinate, N_TiC is direct ratio of approximately linear with temperature, N_TiC is increscent with higher temperature; when the temperature is determinate, N_TiC is less with bigger p_N2.Relationship between TiC,TiN content and components in molten iron, results shows that, under certain temperature, When silicon content, vanadium content are determinate, TiC content is less with higher nitrogen pressure; when nitrogen pressure is determinate, TiC, TiN content are less with increasement of silicon content, vanadium content.