Nucleation and Growth of Atomizing Droplets during Spray Forming

In this paper, the behaviors of nucleation and growth of atomizing droplets were investigated by means of microstructure observation and theoretical analysis. The results showed that. there is a unique heterogeneous nucleation mechanism for atomizing process that pre-solid smaller particles colliding with and embedding in liquid-state larger ones act as heterogeneous nuclei. In addition, the reasons of presenting the dendritic growth was analyzed based on the nonequilibrium solute distribution theory, and the relationship between the microstructural refinement and the cooling rate of the material was given.