Phase-Field Modelling of Intermetallic Solidification

Abstract

Many important intermetallic compounds display a faceted morphology during solidification close to equilibrium but adopt a more continuous, dendritic like morphology with increasing departure from equilibrium. We present a phase-field model of solidification that is able to both reproduce the Wulff shape at low driving force and to simulate a continuous transition from faceted to dendritic growth as the driving force is increased. A scaled ratio of the (perimeter) 2 to the area is used to quantify the extent of departure from the equilibrium shape.

Microstructure modelling for metallic additive manufacturing: a review

“…Comparing the models, PFM not only give realistic dendrite shapes, but it also accounts for the solute distribution between the dendrite arms. When combined with thermodynamic databases, TTT and CTT curves, PFM can have not only very accurate details of solute distribution and dendrite shapes and sizes but also predict the composition of the various metals and intermetallic and transformation and growth of precipitates (Ferreira, Paradela et al 2017, Mullis, Bollada et al 2018, Böttger, Apel et al 2019. All the PFM models for AM were in 2D and only simulated for a few dendrites.…”

Structure evolution in undercooled CoCrNi medium entropy alloys by glass fluxing method

“…This is like the quenching of martensite in steel [40][41] . In the undercooling melt, there is a great driving force for crystal growth [31][32][33][34][35] . If nucleation occurs, the crystal will start to grow at a very fast rate, and then a large amount of crystal will be quickly released during the rapid growth of the crystal.…”

“…If nucleation occurs, the crystal will start to grow at a very fast rate, and then a large amount of crystal will be quickly released during the rapid growth of the crystal. The latent heat of crystallization leads to the re-glow phenomenon, which causes the temperature to rise rapidly until it is near the liquidus line, therefore the newly formed dendrites are under severe overheating, which leads to the occurrence of remelting [34][35] . The remelting of dendrites will lead to the apparent refinement of grains.…”

“…Different from the as-cast sample with solely FCC structure, the sample solidified with a large undercooling of 300 K shows a mixture of FCC and BCC phase [33] . The undercooling method is an effective way to obtain metastable phase and refine grain structure in the solidification treatment [34][35] . The purpose of this paper is to invest the evolution of the microstructure and mechanical properties of CoCrNi ternary medium entropy alloy (MEA) after glass fluxing treatment.…”