Thermodynamic Assessment of Ti-Al-Fe-V Quaternary System Applied to Novel Titanium Alloys Designing

The Ti-Al-Fe-V quaternary system is a very useful system for titanium alloy development. However, there are few reports on the thermodynamic description of this system. In the present work, the experimental investigation and thermodynamic description of the relative sub-systems of the Ti-Al-Fe-V quaternary system are summarized and reviewed, wherein the Ti-Fe-V system is re-assessed by using CALPHAD (CALculation of PHAse Diagrams) approach. The thermodynamic database of the Ti-Al-Fe-V quaternary system is established by extrapolating the thermodynamic descriptions of all sub- systems. Then, a method of titanium alloy design combining Mo equivalent with CALPHAD is proposed. The pseudo-binary sections with V:Fe = 3.5:1 and Al = 0.0, 3.0, 4.5 and 6.0 wt% are calculated. Finally, three different types of titanium alloys are recommended according to the new method.

Automated summary

This study summarizes and reviews the experimental investigation and thermodynamic description of the Ti-Al-Fe-V quaternary system, and re-assesses the Ti-Fe-V system using the CALPHAD approach. It also proposes a method of titanium alloy design combining Mo equivalent with CALPHAD.