TWO VERSIONS OF 3D COMPUTER MODEL OF THE AG-SB-SN PHASE DIAGRAM, DETERMINED BY THE THERMAL STABILITY OF SB3SN4

10.25712/ASTU.1811-1416.2025.01.003

Abstract

The Ag-Sb-Sn system is of interest to microelectronics and is a promising material used in high temperature soldering. The analysis of phase equilibria in the system is difficult because of the lack of an agreed opinion on its structure: various versions are due to an ambiguous description of the formed compounds and the conditions for their existence. Thus, compound Sb3Sn4 is either considered stable up to room temperature or exists in a limited of 323-242^oC temperature range.

The purpose of the work was to analyze phase equilibria in the Ag-Sb-Sn system depending on the method of formation and the temperature boundaries of the existence of the binary compound Sb3Sn4. For this, two versions of a three-dimensional (3D) computer model of the Ag-Sb-Sn phase diagram were constructed. The technology of assembling a phase diagram from surfaces and/or phase regions was used. Iso- and polythermal sections were calculated for both versions of the 3D model. The resulting versions provide a complete geometric description of the phase diagram, including in solid regions. In addition, the model can be adjusted when new experimental information is obtained and even a radical change in the understanding of the properties of compounds formed in the system. Both versions of 3D models expand the predictive functions of the phase diagram, and in the future will help to understand the structure of phase diagrams of other ternary systems formed on the basis of the binary Sb-Sn system.