  We present a new phase field crystal model for structural transformations in
multi-component alloys. The formalism builds upon the two-point correlation
kernel developed in Greenwood et al. for describing structural transformations
in pure materials [Phys. Rev. Lett. 105, 045702 (2010)]. We introduce an
effective twopoint correlation function for multi-component alloys that uses
the local species concentrations to interpolate between different crystal
structures. A simplified version of the model is derived for the particular
case of threecomponent (ternary) alloys, and its equilibrium properties are
demonstrated. Dynamical equations of motion for the density and multiple
species concentration fields are derived, and the robustness of the model is
illustrated with examples of complex microstructure evolution in dendritic
solidification and solid-state precipitation.
