Simulación y desarrollo de aleaciones de alta entropía de bajo punto de fusión para aplicaciones de soldadura sin plomo

Abstract

The use of lead (Pb) in soldering process has been employed since the dawn of modern electronics. As technologies and regulations advance, and concerns for the environment and health become increasingly stringent, the use of lead in soldering has become increasingly controversial. One possible replacement has been the investigation of recently discovered low-melting-point high-entropy alloys (LMP-HEA). In this work, four LMP-HEA candidates in the Ga-In-Bi-Sn-Ag system were evaluated using a theoretical and experimental approach. According to the theoretical approach, thermodynamic models simulated with Thermo-Calc® software were used to obtain compositions and phase diagrams, thus optimizing the search times for LMP-HEA candidates. The most notable composition was Ga5In30Bi30Sn30Ag5, in which a more refined and homogeneous structure was observed by SEM. In wettability tests, the results were favorable, with good spread at contact angles of 52° at a temperature of 180°C, making it a candidate for a welding alloy.