Two stage mass transfer kinetics and control of the deep deoxidation window with low splashing during vacuum final carbon deoxidation of molten steel

作者：Zi Wang, Yu Bao, Zefeng Zhang, M Wang · 发表于：Journal of Materials Research and Technology · 年份：2026 · DOI：10.1016/j.jmrt.2026.07.237 · 研究领域：High-Temperature Coating Behaviors、Metallurgical Processes and Thermodynamics、Corrosion Behavior and Inhibition

Vacuum final carbon deoxidation is regarded as an important route for producing ultra-low oxygen clean steel because its deoxidation product is removed in the form of CO gas and, in principle, does not introduce solid oxide inclusions. However, the process still involves unresolved issues related to deep deoxidation capability, the deoxidation rate at the later stage, and splashing risk under high oxygen conditions. In this study, the effects of ambient pressure, initial oxygen content, and carbon content in molten steel on vacuum final carbon deoxidation behavior were systematically investigated in a 2 kg vacuum induction furnace. A pressure constraint model for CO bubble nucleation was established, and the deoxidation process was divided into an initial exponential decay stage and a later linear stage for quantitative kinetic characterization. The results show that ambient pressure significantly affects the deep deoxidation capability at the later stage. Under pressures of <30 Pa and 5000 Pa, the initial deoxidation rates are similar, whereas both the initial and later stage deoxidation processes are markedly suppressed at 50000 Pa, with the later stage linear deoxidation rate decreasing to only -0.49×10 -6 /min. The initial oxygen content mainly affects the reaction intensity and splashing risk in the early stage. Under high oxygen conditions, the carbon oxygen reaction is violent and prone to cause splashing, whereas initiating vacuum final carbon deoxidation at a medium ...