Hidden Complexity in Stress‐Induced Phase Transformations of CeO 2 –ZrO 2 Ceramics

ABSTRACT Ceria‐doped zirconia exhibits transformation‐induced plasticity, offering a path toward ductile ceramics. However, the atomic‐scale stress‐ and orientation‐dependent transformation mechanisms remain unclear. Here, we use large‐scale atomistic simulations based on a machine‐learning interatomic potential to study uniaxial compressions of pure and ceria‐doped tetragonal zirconia. The simulations reveal a transformation landscape far richer than the commonly assumed direct tetragonal‐to‐monoclinic pathway, with multiple metastable monoclinic and orthorhombic phases acting as intermediate or trapping states. Guided by the martensitic transformation theory, we show how doping and boundary conditions reshape this landscape and affect the resulting transformation strains and critical stresses.