First-principles study on phase stability and elastic properties of Zr-Ti alloy

Abstract:

In this paper, the super-cell model based on SQS methed and first-principles calculation is performed on investigating the influences of Ti concentration and phase structure(hcp and bcc structure )( α and β phase) on phase stability and elastic properties in Zr1-xTix systems.The results show that from the perspective of elastic properties, the structure of Zr-Ti alloy is more stable with the increase of Ti content. The α phase of Zr-Ti alloy generally has higher structural stability than β phase; Zr- Ti alloys generally have ductility. The α phase of Zr-Ti alloy has higher hardness and its hardness and toughness are proportional to the concentration of Ti. From the perspective of electronic structure, the concentration of Ti does not significantly change the DOS of hcp structure and the bcc structure of the Zr-Ti alloy systems.The Fermi level in the DOS distribution of the Zr-Ti alloy system is similar to that of the pure Zr system. Therefore, the content of Ti in the Zr-Ti alloy has little effect on the phase stability of the Zr-Ti alloy.

Key words:First-principles;phase stability;elastic properties;zirconium-titanium alloy