Diffusion, dynamics and solidification processes in Fe-Al-Si melts – SOLIMAT

The present proposal aims at investigating microscopic mechanisms that govern the diffusion dynamics in Fe-Al-Si melts as well as the early stages of solidification of these systems in their undercooled state. The German-French consortium set up a joint experimental and theoretical study for understanding these phenomena in Fe-Al-Si mixtures which is of fundamental and technological interest. State-of-the-art contact-free measurements on metallic liquids are performed, applying both electrostatic and electromagnetic levitation techniques, and using large-scale European facilities to measure high quality structural and dynamic properties in the liquid and undercooled alloys prior to solidification. The obtained experimental data will provide a wide spectrum of thermophysical properties of high-temperature Fe-Al-Si melts, namely density, thermal expansion, shear viscosity, static structure factors, self- and interdiffusion coefficients, and Soret coefficients. These data are associated to a data base from quantum calculations and enable us to construct interatomic force fields using machine learning methodologies based on Artificial Intelligence concepts. With these force fields, a realistic modelling in terms of large-scale molecular dynamics simulations shall be possible. From these simulations, we are aiming at a microscopic insight into kinetic as well as solidification rocesses. Moreover, for the example of the system Fe-Al-Si, the methodology shall be developed to obtain interaction models for ternary metallic systems from machine learning techniques. These interaction models shall provide a realistic description of materials properties of melts as well as of solidification processes and the properties of crystalline phases.