If all the components of a metal alloy are heated to a high enough temperature, they will quickly form an almost perfect homogeneous mixture. If this mixture is then rapidly quenched below a certain temperature, the solution solidifies. Depending on the concentrations of the involved metals, different processes of phase separation may set in. During a process called spinodal decomposition, the components immediately start to separate again, thereby forming a highly inhomogeneous fine-grained structure exhibiting a characteristic length scale. Depending on the relative concentrations of the involved metals, one can observe connected snake-like patterns, or disconnected patterns. The included pictures and movies show the decomposition process and observed patterns for a binary alloy, i.e., an alloy consisting of two metals. The underlying mathematical model is the Cahn-Hilliard partial differential equation.

Pattern in 2D, equal mass: A sample pattern observed on a square domain. The two involved components have equal mass.

Pattern in 2D, different mass: A sample pattern observed on a square domain. The two involved components have different mass.

Evolution in 1D, equal mass: A sample decomposition movie observed for a 1D domain. The two involved components have equal mass.

Evolution in 2D, equal mass: A sample decomposition movie observed on a square domain. The two involved components have equal mass.

Evolution in 2D, different mass: A sample decomposition movie observed on a square domain. The two involved components have different mass.