Ab initio-aided CALPHAD thermodynamic modeling of the Sn-Pb binary system under current stressing

Shih Kang Lin, Chao Kuei Yeh, Wei Xie, Yu Chen Liu, Masahiro Yoshimura

Research output: Contribution to journalArticle

11 Citations (Scopus)


Soldering is an ancient process, having been developed 5000 years ago. It remains a crucial process with many modern applications. In electronic devices, electric currents pass through solder joints. A new physical phenomenon - the supersaturation of solders under high electric currents - has recently been observed. It involves (1) un-expected supersaturation of the solder matrix phase, and (2) the formation of unusual "ring-shaped" grains. However, the origin of these phenomena is not yet understood. Here we provide a plausible explanation of these phenomena based on the changes in the phase stability of Pb-Sn solders. Ab initio-aided CALPHAD modeling is utilized to translate the electric current-induced effect into the excess Gibbs free energies of the phases. Hence, the phase equilibrium can be shifted by current stressing. The Pb-Sn phase diagrams with and without current stressing clearly demonstrate the change in the phase stabilities of Pb-Sn solders under current stressing.

Original languageEnglish
Article number2731
JournalScientific reports
Publication statusPublished - 2013 Oct 8


All Science Journal Classification (ASJC) codes

  • General

Cite this