Thermodynamic description of Cr-P AND Fe-Cr-P systems at low phosphorus contents

Thermodynamic optimization of systems Cr-P and Fe-Cr-P has been made by using classical thermodynamic models for describing the properties of the individual phases of the systems. The thermodynamic parameters of sub-systems Fe-Cr and Fe-P for Fe-Cr-P were taken from earlier assessments and the parameters of systems Cr-P and Fe-Cr-P were optimized by using recently measured activity and Gibbs energy data, and experimental phase equilibrium data. The present descriptions are valid at phosphorus contents up to Xp=0.25 (≈16.6 wt%P).