Secondary liquid separation and solidification of Cu-Co alloys under deep supercooling

The secondary liquid separation and solidification behaviors of Cu-(10% ∼ 30%)Co alloys under deep supercooling were investigated by means of fluxing glass deep supercooling technology and metallographic analysis. The results reveal that Cu is continuously separated from Co-rich liquid as temperature decreasing. If Cu atoms can not diffuse into Cu-rich liquid phase, new Cu-rich liquid drops will form. Not all of Cu-rich phases in Co-rich matrix come from the secondary liquid separation, one originates select solidifying and another result from Co-rich clusters growing. The cooling curves of alloys reveal that the crystallizing temperature of Co-rich phase is different with the variations of the composition and experiment condition. Peritectic reaction will occur after solidification of Co-rich liquid drops.