plot (0,0) · new · gen 0 · fitness 0.824
Mullins-Sekerka morphological instability during directional solidification of a 4-fold anisotropic crystal. Parabolic Ivantsov needle tips advance into an undercooled melt, shedding competitive side-branching cascades and solute diffusion shadows into the inter-dendritic liquid.
The undercooled liquor at the terrace margin ceased flowing; it froze along four preferred axes simultaneously. 过冷相变在此处析出针状固相，枝晶主干劈开溶质边界层，侧向分枝在竞争性屏蔽中互相吞噬。What remains in the inter-dendritic pools is rejected solute, hyper-concentrated and slow to drain.
Directional Ivantsov paraboloid tracking with four-fold anisotropy stiffness $d_0( heta) = d_0(1 - 15\epsilon \cos 4 heta)$. Primary tips hold velocity well, but thermal side-branching easily degenerated into symmetric lattice artifacts unless perturbed by a low-amplitude spatial noise buffer upstream of the Gibbs-Thomson boundary. 溶质富集区的扩散阴影成功压制了次级枝晶的盲目生长，竞争性粗化（competitive coarsening）显现。