Molecular dynamics simulation of the structure and transport properties of Fe–Mn melts

This work uses molecular dynamics to probe structure, self-diffusion and viscosity of Fe–Mn melts across Mn contents and temperatures. Simulated diffusion and viscosity agree with literature. Increasing Mn densifies Mn-centred coordination and loosens Fe-centred coordination; rising temperature weakens bonding, while coordination numbers remain nearly constant. Mean-square displacements show liquid behaviour, with D Mn > D Fe ; both D increase with Mn content and temperature. Viscosity from Green–Kubo correlates closely with reverse nonequilibrium MD (RNEMD); RNEMD resolves composition trends more clearly. At 1950 K, RNEMD predicts viscosities of 6.903, 6.496, 5.958 and 5.570 mPa·s for 3, 6, 9 and 12 wt% Mn, respectively. Lower viscosity implies enhanced fluidity and faster homogenisation (less argon stirring), but greater risks of slag entrainment and refractory erosion, while reducing nozzle clogging. These trends provide reliable property inputs and a theoretical basis for Fe–Mn process design.