Titanium distribution ratio is a key parameter which directly reflect the ability to remove titanium in the LF refining process. A thermodynamic model for calculating the titanium distribution ratio (LTi) between ladle furnace (LF) refining slags, i.e., CaO–SiO2–MgO–FeO–(CaF2)–MnO–Al2O3–TiO2 slags, and molten steel has been developed by coupling with the ion and molecule coexistence theory (IMCT) and slag–metal equilibrium theory. The reliability of the model was verified by comparing it with industrial data. Using this model, the effects of Al, Si content in steel and CaO, MgO and TiO2 in slag on the LTi were investigated. Meanwhile, the optimal equilibrium slag composition of GCr15SiMn bearing steel was predicted. On this basis, five groups of industrial tests were carried out, and the results indicated that the optimized practice had achieved remarkable results in limiting titanium content compared with the routine process.
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