Production of rapidly solidified Cu–Sn ribbons by water jet cooled rotating disc method

In order to obtain rapidly solidified ribbons, it is important to control and understand the mechanism of ribbon formation. In this study, rapidly solidified Cu–Sn ribbons were produced by water jet cooled rotating disc method. The produced ribbons had typically 15–95 μm thickness, 3–6 mm width and 45–72 mm length depending on process parameters. Increasing the disc speed from 50 to 75 m s−1 resulted in a decrease of ribbon thickness from 75 to 34 μm. From the disc-side to the air-side surface of the ribbons, the microstructure of the ribbons consisted of three distinct zones: fine grained microstructure (chill region), columnar zone and cellular/equiaxed region. The columnar zone/ribbon thickness ratio decreased with increasing ribbon thickness. The estimated cooling rates of 20 and 90 μm thick ribbons were 1.98 × 106 and 5.49 × 103 K s−1, respectively.