Eutectic Alloys in the Sn-Zn-Mg-Al System with Eutectic Temperature of 454 K

Abstract

We have experimentally found a Sn-Zn-Mg 2 Sn eutectic alloy with the eutectic composition of 82Sn-10Zn-8Mg (mol%) and with nearly the same eutectic temperature of 454 K as that of the Pb-Sn eutectic alloy. The eutectic alloy was made in air by covering Sn, Zn and Mg with the 59KCl-41LiCl (mol%) composition eutectic melt in an Al 2 O 3 crucible, melting the metals at 1073 K and washing away the alkali-chlorides with distilled water after cooling to room temperature. The as-cast alloy easily oxidized at temperatures above 503 K in air after melting. It was found that the Sn-Zn-(Mg, Al) 2 Sn eutectic alloys that were made by replacing 0.8 to 4.0 mol% of Mg with Al in the ternary eutectic composition with the same alloying method did not oxidize in air after melting.