The Thermodynamic Database for the Development of Modern Lead-Free Solders

Abstract

The methods for the modeling of thermodynamic properties of multicomponent systems are described here. The rules for the creation of a consistent database for multicomponent systems are described generally and documented on the Thermodynamic Database for Lead-free Solders developed in the scope of COST 531 Action. The reassessment of the Sb-Sn system is shown as an example, illustrating the application of consistency rules.

Calphad-type assessment of the Sb–Sn–Zn ternary system

“…According to most thermodynamic descriptions, the Sb 2 Sn 3 phase decomposes by a eutectic reaction at about 240°C, while according to Chen et al [12] this phase is stable at room temperature. In this work, the phase diagram of Kroupa and Vizdal [3] was chosen because one of our aims was to keep consistency with other ternary systems included in the SOLDERS database [2]. There are several ternary systems included there (e.g.…”

“…The stable phases occurring in the Sn-Sb system are BCT_A5, Several CALPHAD type assessments exist also for the Sb-Sn binary system [2,3,[11][12][13]. The thermodynamic dataset used in the SOLDERS database [2] was based on the work of Oh et al [11].…”

“…The thermodynamic dataset used in the SOLDERS database [2] was based on the work of Oh et al [11]. Since different unary data from Dinsdale [13] were used, this system was reassessed by Kroupa and Vizdal [3] and the description was used in the SOLDERS database [2]. According to most thermodynamic descriptions, the Sb 2 Sn 3 phase decomposes by a eutectic reaction at about 240°C, while according to Chen et al [12] this phase is stable at room temperature.…”

“…The relevant binary phase diagrams for Sn-Zn, and Sb-Sn were taken from the SOLDERS database [2], and were originally published in the scientific literature [3,4]. The assessment of the Sb-Zn system was published by Li [5].…”

3D Computer Models of the Ag-Sb-Sn and MgO-Al2O3-SiO2 T-x-y Diagrams

“…3a). In another version with two eutectoid reactions E1 and E2, constructed according to [5,17], the 3D model consists of 109 surfaces and 66 phase regions. Consequently, the conditions for the compound Sb 2 Sn 3 existence require additional experimental study.…”