分野別セミナー

Todays materials industries experience a strong pressure to
develop advanced materials with special purpose properties at
successively decreasing time scales. Multi-scale simulation
approaches can provide support by predicting a multitude of
material properties for specific processing and material
parameters. In particular it is well known, that the mechanical
material properties of a material sample after solidification
are strongly tied to its microstructure structure. Nevertheless,
the precise laws governing the initial stage of this structuring
process, i.e., nucleation and the successive transient
microstructure evolution scenario's, are still far from being
fully understood.
Here we show, that the phase field method [1], which originally
established itself to tackle the free boundary problem given by
microstructure evolution in a multi-physics environment, can
also be employed to investigate the energetics of heterogenous
nucleation in a solidifying sample [2]. Moreover it is
demonstrated, how the phase field crystal method can shed more
light in open questions regarding a quantitative formulation of
nucleation statistics to thereby simulate the phase transition
phenomena in solidification from nucleation to crystallization
in larger domains thoroughly [3,4].
In the talk special emphasis is put on pointing out for what
kind of input the phase-field respectively the phase-field
crystal approach depend on ab-initio input to achieve a multi-
scale simulation approach.
[1] see e.g. H. Emmerich, Advances in Physics 57, 1 (2008)
and references therein
[2] H. Emmerich, R. Siquieri, J. Phys.: Condens. Matter 18,
11121 (2006)
[3] E. Doernberg, R. Siquieri, R. Schmid-Fetzer, H. Emmerich,
accepted for publication in JPCM
[4] R. Prieler, B. Verleye, R. Haberkern, D. Li, H. Emmerich,
submitted to JPCM