Thermodynamic Prediction of Selective Oxidation Windows in Cu–Sn Alloys Using Composition-Dependent CALPHAD Solution Models

Manasijević, Dragan

doi:10.1007/s11085-026-10470-7

Article Metadata only M22

2026

Manasijević, Dragan

Springer Nature

High Temperature Corrosion of Materials

103

107

English

M22 - Paper in a prominent international journal

In the present work, the selective oxidation behavior of Cu–Sn alloys was investigated using an integrated CALPHAD–HSC thermodynamic approach. Phase constitution and temperature- and composition-dependent activities of Cu and Sn were calculated using the assessed COST 531 thermodynamic database, while oxide stability, equilibrium oxygen partial pressures, and metal–oxide–gas equilibria were evaluated using HSC Chemistry. Activity-corrected oxidation boundaries were constructed to quantify selective oxidation windows as functions of alloy composition and temperature. The results demonstrate that non-ideal interactions substantially influence the predicted oxidation windows. In addition, the Redlich–Kister (RK) parameters describing the liquid Cu–Sn phase were implemented directly into HSC Chemistry through a dedicated activity-coefficient model, enabling self-consistent recalculation of Cu and Sn activities during Gibbs energy minimization. Equilibrium predictions at 1100 °C were compared using three treatments of the liquid phase: ideal solution behavior, fixed CALPHAD-derived activity coefficients, and the self-consistent CALPHAD–RK model. The three metallic-phase treatments produce only limited differences in the equilibrium oxidation degrees at 1100 °C. The self-consistent treatment provides the most conservative predictions, with slightly lower Sn oxidation and somewhat greater Cu oxidation than the simpler treatments. The influence of composition-dependent activity updating is most pronounced in dilute Cu–Sn alloys and during the final stage of Sn removal. This study provides a systematic computational assessment of composition- and temperature-dependent selective oxidation in Cu–Sn alloys and quantifies the influence of alternative metallic-phase descriptions on the predicted Sn-removal/Cu-loss relationship.

451-03-34/2026-03/20013

Cu–Sn alloys, High-temperature oxidation, Selective oxidation, CALPHAD, Oxygen potential, Activity coefficients

DOI

10.1007/s11085-026-10470-7

ISSN

2731-8400
2731-8397

URI

https://repozitorijum.tfbor.bg.ac.rs/handle/...

Scopus Web of Science OpenCitations OpenAlex

dc.creator	Manasijević, Dragan
dc.title	Thermodynamic Prediction of Selective Oxidation Windows in Cu–Sn Alloys Using Composition-Dependent CALPHAD Solution Models
dc.date.issued	2026
dc.publisher	Springer Nature
dc.identifier.doi	10.1007/s11085-026-10470-7
dc.identifier.issn	2731-8400
dc.identifier.issn	2731-8397
dc.type	article
dc.source	High Temperature Corrosion of Materials
dc.citation.volume	103
dc.citation.spage	107
dc.language.iso	en
dc.type.version	publishedVersion
dc.citation.rank	M22
dc.citation.ifactor	2.2
dc.subject	Cu–Sn alloys
dc.subject	High-temperature oxidation
dc.subject	Selective oxidation
dc.subject	CALPHAD
dc.subject	Oxygen potential
dc.subject	Activity coefficients
dc.description.abstract	In the present work, the selective oxidation behavior of Cu–Sn alloys was investigated using an integrated CALPHAD–HSC thermodynamic approach. Phase constitution and temperature- and composition-dependent activities of Cu and Sn were calculated using the assessed COST 531 thermodynamic database, while oxide stability, equilibrium oxygen partial pressures, and metal–oxide–gas equilibria were evaluated using HSC Chemistry. Activity-corrected oxidation boundaries were constructed to quantify selective oxidation windows as functions of alloy composition and temperature. The results demonstrate that non-ideal interactions substantially influence the predicted oxidation windows. In addition, the Redlich–Kister (RK) parameters describing the liquid Cu–Sn phase were implemented directly into HSC Chemistry through a dedicated activity-coefficient model, enabling self-consistent recalculation of Cu and Sn activities during Gibbs energy minimization. Equilibrium predictions at 1100 °C were compared using three treatments of the liquid phase: ideal solution behavior, fixed CALPHAD-derived activity coefficients, and the self-consistent CALPHAD–RK model. The three metallic-phase treatments produce only limited differences in the equilibrium oxidation degrees at 1100 °C. The self-consistent treatment provides the most conservative predictions, with slightly lower Sn oxidation and somewhat greater Cu oxidation than the simpler treatments. The influence of composition-dependent activity updating is most pronounced in dilute Cu–Sn alloys and during the final stage of Sn removal. This study provides a systematic computational assessment of composition- and temperature-dependent selective oxidation in Cu–Sn alloys and quantifies the influence of alternative metallic-phase descriptions on the predicted Sn-removal/Cu-loss relationship.
dc.relation	451-03-34/2026-03/20013
dc.rights.license	ARR
dc.rights.uri	https://repozitorijum.tfbor.bg.ac.rs/all-rights-reserved
dc.date.accessioned	2026-10-27T12:26:12Z
dc.description.provenance	Submitted by dmanasijevic@tfbor.bg.ac.rs on 2026-10-22 07:39:49.384024, with 0 file(s). Approved by Милица Ницуловић (mniculovic@tfbor.bg.ac.rs) on 2026-10-27T12:26:12Z.
dc.identifier.uri	https://repozitorijum.tfbor.bg.ac.rs/handle/123456789/6163


Thermodynamic Prediction of Selective Oxidation Windows in Cu–Sn Alloys Using Composition-Dependent CALPHAD Solution Models	7