Microstructure Evolution in a Rapidly Solidified Cu_(85)Fe_(15) Alloy Undercooled into the Metastable Miscibility Gap

摘要

A model has been developed to describe the microstructure evolution in the atomized droplets of Cu-Fe alloy during cooling through the metastable miscibility gap. Calculations have been performed for Cu_(85)Fe_(15) alloy to investigate the process of liquid-liquid phase transformation. The numerical results indicate that the minority phase droplets are nucleated in a temperature region around the peak of the supersaturation. The average radius of the Fe-rich droplets decreases and the number density of the minority phase droplets increases with decreasing the atomized droplet size. The simulated results were compared with the experimental ones. The kinetic process of the liquid-liquid phase transformation was discussed in detail.