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This study investigated the influence of Sb addition on the microstructure, thermal behavior, mechanical properties, and interfacial evolution of SAC305-2Bi-xSb/Cu solder joints. Compared with the SAC305-2Bi alloy, the melting temperature and pasty range slightly increased with the increasing of Sb content from 0.2 to 2.0 wt.%, while the undercooling temperature decreased. The research revealed that with the addition of Sb element, the grain size of β-Sn is refined. When the content of Sb is 0.5 wt.%, the grain size of β-Sn reached minimum (19.91 μm). Compared to the SAC305-2Bi alloy, the ultimate tensile strength of SAC305-2Bi–2Sb alloy is increased by 30.10%, contributed to the Sb solid solution strengthening effect and the refinement of β-Sn. With the addition of Sb, the thickness and growth rate of the interface is reduced gradually. The uniform solution of Sb and Sn can significantly inhibit the diffusion rate of Cu atoms and Sn atoms at the interface. The SAC305-2Bi-xSb alloy system has low melting temperature, superior mechanical properties, and reliable solder joints for service. Therefore, it is a potentially reliable lead-free solder for high-stability connections in automotive electronics, communications electronics, and medical devices.

PbTe based materials are well known for their high performance thermoelectric properties. Here, a systematic study of thermoelectric transport properties of n-type Pb-deficit Pb 0.98-x Sb x Te alloys with carrier concentrations in the range of ∼10 −19 cm −3 is presented from room temperature to 623 K. A maximum thermoelectric figure of merit (zT) of ∼0.81 was achieved at 623 K for 4 mol% Sb containing Pb-deficit composition, by the cumulative integration of enhanced power factor and significant reduction in thermal conductivity. The scattering of phonons at Pb vacancies, contributed to the reduction of lattice thermal conductivity, and thereby strikingly boosted the zT of the Pb-deficit samples when compared with the pristine Pb 1-x Sb x Te. [ABSTRACT FROM AUTHOR]