Formation of macroscopically phase separated Cu-colored melt-spun ribbon in (Fe_(0.5)Cu_(0.5))_(100-x)B_x (x = 0, 5,10, and 20) alloys

摘要

The microstructure of a rapidly solidified melt-spun ribbon of binary Fe-Cu and ternary Fe-Cu-B alloys was investigated. The duplex structure composed of Fe-B-rich and Cu-rich alloys was formed by liquid phase separation of Fe-Cu-B alloys regardless of the B content. We found that the element Cu shows a strong tendency to segregate on the surface of Fe-Cu-B alloy ribbons, resulting in the formation of a macroscopically phase-separated Cu-colored cover layer/core structure.