Abstract
A new method of an extremely efficient process of purification of metals and metaloids, called normal segregation or zone melting, has been developed in recent few years and its principle and practical application chiefly on semiconductors have been reported by a number of investigators. But very few experiments have been carried out on common metals. The purpose of the present paper is to deduce a fundamental data of normal segregation on ordinary alloys, such as Cu-Sn and Cu-Ni systems. The former has a segregation coefficient smaller than 1 (0.09∼0.2) and the latter greater than 1 (2.1∼2.7). The results obtained are shown in Figs. 3∼8, comparing the experimental data with the theoretical formula given by W. G. Pfann. As can be seen in these figures, the freezing rate of alloys remarkably influences the purification degree, resulting in a great deviation of experimental plots from the theoretical curve.
