Scale-Bridging Thermodynamic and Kinetic Simulation (STKS)
Diffusivities of an Al-Fe-Ni melt and their effects on the microstructure during solidification
L. Zhang, Y. Du, I. Steinbach, Q. Chen, B. Huang.
Acta Materialia, 58, 3664-3675, (2010)
A systematical investigation of the diffusivities in an Al–Fe–Ni melt was presented. Based on the experimental and theoretical data about diffusivities, the temperature- and composition-dependent atomic mobilities were evaluated for the elements in Al–Ni, Al–Fe, Fe– Ni and Al–Fe–Ni melts via an eﬀective approach. Most of the reported diffusivities can be reproduced well by the obtained atomic mobilities. In particular, for the ﬁrst time the ternary diffusivity of the liquid in a ternary system is described in conjunction with the established atomic mobilities. The eﬀect of the atomic mobilities in a liquid on microstructure and microsegregation during solidiﬁcation was demonstrated with one Al–Ni binary alloy. The simulation results indicate that accurate databases of mobilities in the liquid phase are much needed for the quantitative simulation of microstructural evolution during solidiﬁcation by using various approaches, including DICTRA and the phase-ﬁeld method.
Keyword(s): Al-Fe-Ni melt; Diffusion; Atomic mobility; Microstructure; Solidification