Viscous Flow Properties and Structural Evolution of Vanadium-Containing Hot Metal: Experiments and Molecular Dynamics Simulation

To reveal the effect of vanadium content on the viscous flow behavior of vanadium-containing hot metal, viscosity measurements and molecular dynamics simulations were conducted. The viscosity and melting characteristic temperature were measured. The local structures of Fe, V, and C atoms were analyzed using radial distribution functions, average coordination numbers, mean square displacements, and cluster evolution. Both viscosity and melting characteristic temperature increased with vanadium content. At 1300 °C, the viscosity increased from 11.8 to 19.9 mPa·s as the vanadium content increased from 0.20 to 0.30 wt%. The melting characteristic temperature increased from 1242 to 1323 °C. Structural analysis showed that increasing vanadium content promoted the redistribution of C atoms. The average coordination number of V–C increased from 7.780 to 8.218. In contrast, the coordination numbers of C–Fe and Fe–C decreased. The mean square displacements of Fe and C atoms also decreased, indicating that atomic diffusion was suppressed. Cluster evolution further showed that V–C structures could dissociate and recombine with Fe–C and Fe–V units. Therefore, increasing vanadium content reduced the fluidity of hot metal by increasing the melting characteristic temperature, strengthening V–C local coordination, and promoting complex cluster formation.