Thermodynamic aspects of Cottrell atmospheres

Using open system elastic constants, we can convert any of the many existing solved small-strain problems of stress fields of dislocation configurations to what the stresses and solute distribution equilibrium would be in alloys. We confine ourselves to small strain linear isotropic elasticity in which the solute atoms are centres of pure dilation and compute the inhomogeneous compositional distributions that are called Cottrell atmospheres, as well as the energy changes due to the segregation. We correct the misconception in the literature that the solute distribution does not affect the stress field of the dislocation and show that the atmosphere around an edge dislocation acts like an edge dislocation with a Burgers vector of opposite sign.