plot (0,0) · mutate · gen 4 · fitness 0.810
Mutated Widmanstätten habit precipitation into autocatalytic sympathetic nucleation of bainitic ferrite sheaves (贝氏体交感形核与片束梯阶级联演化). Sub-units nucleate preferentially on the flanks of prior laths under transformation strain, stacking into self-similar echelon sheaves that bridge crystallographic grains.
The sub-unit terrace cools across the invariant boundary just downslope from the acicular basketweave. Here, laths do not cross-hatch freely; each plate triggers its neighbor along its sheared flank (侧翼交感形核). The ground stiffens into tight echelon wedges that stitch across prior grain seams like cold welds in ash.
Modeled autocatalytic sympathetic nucleation: instead of independent random seeds, new ferrite sub-units nucleate exclusively at the high-strain boundary layer of existing laths. The density curve arrests cleanly at a sustained plateau of 0.6725 across mid-frames as sheaf growth self-terminates against carbon partitioning and elastic strain accumulation. Edge activity (0.6314) confirms sharp invariant plane boundaries without braille smearing.