Solidification Overview

Principles

Definition

Solidification is an academic concept investigating the processes through which dynamic or fluid entities, structures, or patterns within a system transition into stable, defined, and enduring forms. This concept examines the mechanisms, conditions, and implications of such transitions, focusing on the establishment of fixed boundaries, formalized rules, or persistent configurations.

Ontological type

Physical Mechanisms

Thermodynamic Conditions

Microstructural Evolution

Key developments

Key Figures

Interfacial Morphology Theory era

Mullins and Sekerka developed the diffusion-controlled stability analysis of a solidifying planar front, deriving the Mullins-Sekerka criterion that explains when a flat interface remains stable or gives rise to cellular and dendritic morphologies. Rosenthal's dendritic-growth perspective linked undercooling and diffusion to patterned solidification, providing an early architectural framework for interfacial morphology. Cahn and Hilliard introduced a diffuse-interface, free-energy approach in the late 1950s that formalized how interfacial energy and composition gradients govern pattern formation during solidification and phase separation. Together with metallurgical crystallography influences of the period, these authors shaped a cohesive program in which interfacial control drives the selection of dendritic versus cellular morphologies.

Non-equilibrium Interface Kinetics era

A. Needleman [1] is associated with Technical University of Denmark [3] and Brown University [4] during this era. His key contribution is the continuum model for void nucleation by inclusion debonding [7], a framework that quantifies nucleation events and defect formation during rapid solidification. M. Rappaz [2] is associated with École Polytechnique Fédérale de Lausanne [5] and Aarhus University [6] during this era. His contribution is the probabilistic modelling of microstructure formation in solidification processes [8], demonstrating how stochastic treatments can predict microstructure evolution under non-equilibrium solidification and informing interface-kinetics models.

Computational Microstructure Engineering era

Long‐Qing Chen [1], with affiliations at Northwestern University [2] and Hefei University [3], is a central figure in the Computational Microstructure Engineering era. His Phase-Field Models for Microstructure Evolution [4] advanced phase-field formulations as practical diffuse-interface tools, enabling multi-physics simulations that couple heat transfer, solute transport, and nucleation to predict casting, welding, and additive manufacturing outcomes; this work was pivotal for enabling computational design of microstructures in this era. Chen's work bridged theory and computation to make microstructure design a programmable lever in materials science, a hallmark of this era [1]. The approach laid the groundwork for later diffuse-interface platforms and process-structure design strategies that tie microstructure evolution to processing conditions, cementing Chen's influence on computational microstructure engineering [1].