Microstructure analysis of Co–Cu alloys undercooled prior to solidification

Co41.8Cu58.2 and Co16Cu84 alloys were investigated by electromagnetic levitation (EML) and drop tube (DT) processing. The experiments show that both methods allow deep undercooling of the alloys into the miscibility gap. By electromagnetic levitation, in Co41.8Cu58.2 alloy the distribution of Co-rich phases was strongly influenced by electromagnetic stirring, while in Co16Cu84 alloy the Co-rich phases exhibit rounder shape. By drop tube experiment, the disturbance of the electromagnetic stirring is reduced, the Co-rich phases distribute homogeneously in the matrix phase.