Molecular dynamics simulation of morphological instabilities in solid-fluid interfaces

We perform molecular dynamics simulations of directional growth of a binary alloy. We fix the temperature gradient, pulling speed, impurity concentrat ion and only vary the impurity segregation coefficient, By changing the ran ge of the Lennard Jones potential of impurity atoms as compared to the rang e of the potential of solvent atoms, the elastic energy cost causes a decre ases of solubility of the impurity atoms into the matrix (solvent) solid ph ase and consequently a decrease in the impurity segregation coefficient. Wi thin certain range of segregation coefficients, the growing interface is pl anar; below it, the interface becomes unstable and a cellular structure eme rges.