Abstract Scope |
Defects can be chemically manipulated by solute decoration through partitioning between defect and matrix at equal chemical potential. Such Gibbsian equilibrium segregation effects do not only lead to strong confined partitioning but also to low-dimensional transformations, altering the defects’ energy, mobility, structure, and cohesion. Some of these phenomena have been described already long ago: Examples are Cottrell atmospheres at dislocations, Suzuki partitioning to stacking faults and grain boundary segregation according to the adsorption isotherm. However most of these models only consider interaction-free partitioning, with the implicit assumption that the decorated defects behave like low-dimensional solid solutions. The lecture shows that real segregation phenomena are thermodynamically far more complex, characterized by substantial interaction among the segregating species, leading to a wide variety of low-dimensional phase-like states. |