2D Terfenol-D Domain-Lattice Actuator

This is a genuinely 2D companion to the 3D Terfenol-D magnetostrictive actuator, not a flattened view of it. Instead of evaluating a single algebraic strain-vs-field formula instantly, this version simulates a lattice of coupled magnetic domains, each with its own slightly disordered local anisotropy and a finite relaxation time toward the field-aligned state. Watch the domain lattice's switching front sweep across the grid as the field ramps, and watch the strain-vs-field phase portrait open into a real hysteresis loop at high drive frequency and collapse back onto the 3D model's quasi-static curve at low frequency — an emergent effect the instantaneous 3D formula cannot show.