A simple numerical scheme was presented to simulate partial equilibrium solidification with complete interstitial and negligible substitutional solute back diffusion in multi-component and multi-phase systems. Based on this scheme, a computing tool capable of using Thermo-Calc databases directly was developed for the estimation of solidification behavior of steels and other interstitial-containing alloys. Agreements between calculated and experimental as well as DICTRA results were obtained on the micro-segregation, fraction of eutectic, and freezing range of several steels. This suggested that the partial equilibrium assumption and proposed numerical scheme were reasonable and satisfactory, and confirms that the C back diffusion plays a very important role in the solidification of steels.

Computation of Partial Equilibrium Solidification with Complete Interstitial and Negligible Substitutional Solute Back Diffusion. Q.Chen, B.Sundman: Materials Transactions, 2002, 43[3], 551-9