Effects of Superheat and Volume Fraction in the Mixalloying Process

Abstract

Dispersed-phase microstructures of Pb-Zn, Pb-Zn-Sn, and Pb-Al immiscible alloys were produced by the Mixalloying process. The superheat and the volume fraction of the impinging metal jets were systematically varied and their effects on the resulting microstructures were examined. High superheats resulted in coarse microstructures. At lower volume fractions of the second-phase, particles of the minor phase were well dispersed. As the volume fraction approached 0.5, however, the structure became interconnected. The minor phase size, defined either as the mean particle diameter or the mean linear intercept, followed the log-normal distribution, and was the smallest in the Pb-Zn-Sn system for the entire volume fraction range.