Institut für Angewandte Materialien – Werkstoffkunde

Project 9: Phase-field simulations of multiphase microstructure evolution in binary and ternary Mo- Ti-Si-(B)

M.Sc. Yuhan Cai

Supervisors: Prof. Britta Nestler, Prof. Hans Jürgen Seifert

Support by assoc. members: Dr. Michael Kellner

The aim of this subproject is to employ large-scale material computations for a systematic investigation on the evolution of the multiphase microstructures in the high temperature alloys Mo-Ti-Si-(B). The phase-field model has been proven to be a powerful modeling technique to simulate the microstructural evolution during solidification in the past two decades. In combination with high performance computing techniques, a phase-field approach based on the grand potential formulation is employed for large-scale (3D+t) simulations of the evolution of intermetallic compounds in this alloy system Mo-Si-Ti-(B). However, for the case of phases with stoichiometric components, which lacks sufficient thermodynamic data, a special treatment is needed to characterize their properties and to model their evolution correctly. By incorporating anisotropic interfacial and kinetic properties, the methods are capable to analyze the influence of interfacial energies and interdiffusion on the pattern formation. Large scale microstructure simulations on high performance computing facilities will enable us to model a large space of characteristic microstructure patterns under controlled processing conditions and to derive respective morphology diagrams.