Kinetic theory of nucleation and coarsening

Nanovoid nucleation by vacancy aggregation and vacancy-cluster coarsening in high-purity metallic single crystals

A numerical model to estimate critical times required for nanovoid nucleation in high-purity aluminum single crystals subjected to shock loading is presented. We regard a nanovoid to be nucleated when it attains a size sufficient for subsequent growth by dislocation-mediated plasticity. Nucleation is assumed to proceed by means of diffusion-mediated vacancy aggregation and subsequent vacancy cl...

Effect of Different Nucleation and Growth Kinetic Terms on Modeling Results of KNO3 CMSMPR Crystallizer

An analysis of two classes of phase field models for void growth and coarsening in irradiated crystalline solids

A formal asymptotic analysis of two classes of phase field models for void growth and coarsening in irradiated solids has been performed to assess their sharp-interface kinetics. It was found that the sharp interface limit of type B models, which include only point defect concentrations as order parameters governed by Cahn-Hilliard equations, captures diffusion-controlled kinetics. It was also ...

Interface Anisotropy and its Effect on Microstructural Evolution During Coarsening

The driving force for coarsening is provided by the excess interfacial free energy. In a system with isotropic interface energies, classical coarsening theories can predict the evolution of the sizes of spherical crystals. However, if the interfaces are anisotropic, crystal growth and shrinkage may be limited by the surface attachment/detachment rate, the motion of ledges, or the nucleation of ...

Formation and coarsening of Ag(110) bilayer islands on NiAl(110): STM analysis and atomistic lattice-gas modeling

Scanning tunneling microscopy analysis of the initial stages of film growth during deposition of Ag on NiAl(110) reveals facile formation of bilayer Ag(110) islands at temperatures of 130 K and above. Annealing subsequent to deposition at 130 K induces coarsening of the bilayer island distribution. The thermodynamic driving force for bilayer island formation reflects a lower relative surface en...