Effect of foreign particles on the dendritic growth in phase-field theory

The presence of foreign particles in the undercooled melt can influence the evolution of solidification structure and change the dendritic morphology. In this work, according to the KKS model, a hybrid phase field model for binary alloys, which takes into account the random crystallographic orientation, is developed to analyze the effect of misorientation between foreign particles and crystal grains on the dendritic growth. The simulation results show that the influence of foreign particles depends on the particle size, position, numbers and the degree of misorientation. The foreign particles which do not match the initial orientation of the crystal cause the dendrite trunks to deflect and split, leading to the formation of irregular dendritic morphology.