Crystal Nucleation & Growth
Simulating solidification: nuclei form stochastically, then grow outward with preferred crystallographic orientations. Competing grains form grain boundaries.
Grains: 0
Crystallized: 0%
Step: 0
Classical Nucleation Theory
Nucleation rate J ∝ exp(−ΔG*/kT) where ΔG* is the free-energy barrier for a critical nucleus. Above the barrier, growth is thermodynamically favorable. Each grain has a random crystallographic orientation (angle), causing anisotropic growth: fastest along preferred lattice directions. Where expanding grains meet, grain boundaries form — regions of mismatch causing mechanical weakness and chemical reactivity. The Avrami equation describes fraction crystallized: X(t) = 1 − exp(−Kᵐtⁿ).