Thermodynamic Description of Systems Cu-Al-Sn, Cu-Al-Zn and Cu-Sn-Zn in the Copper=Rich corner of the Systems.

摘要

Thermodynamic optimization of systems Cu-Al-Sn, Cu-Al-Zn and Cu-Sn-Zn is made by using classical thermodynamic models for describing the properties of the individual phases of these systems. The optimization is limited to the copper-rich corner of the systems the gamma phase of systems Cu-Al, Cu-Sn and Cu-Zn being the remotest phase included in the analysis. The data for the pure components and for the binary systems are taken from the earlier assessed, SGTE-compatible descriptions, though slight reoptimization of the data is first made for the bcc and fcc phases of the system. Next, new thermodynamic data are optimized for the ternary systems and tentatively, also for the quaternary Cu-Al-Sn-Zn system. The experimental data applied in the optimization are based on the measurements of phase equilibria and various thermodynamic properties obtained from the literature. The results of the optimization are presented by comparing the original, experimental data with the calculations of the present and the earlier studies. Better agreement is obtained by the present calculations through this is due to the smaller validity region (in composition) for the present assessments.