Prediction of Solid-Liquid Interfacial Energy of Steel during Solidification and Control of Dendrite Arm Spacing

Solid-liquid interfacial energy of steel during solidification was measured predicted from the both experimental techniques of unidirectional solidification and thermal analysis applying the dendrite growth model and heterogeneous nucleation model. Solid-liquid interfacial energy changed depending on primary phase during solidification, i.e., that of primary delta phase was larger than that of gamma phase. When the primary phase was the same, solid-liquid interfacial energy increased with increasing carbon content. Primary dendrite arm spacing changed depending on solid-liquid interfacial energy. A trace amount of bismuth which had the effect of a decrease in the solid-liquid interfacial energy of steel during solidification decreased primary and secondary dendrite arm spacing, significantly.