BCC Structural Stability and Deformation Behavior of Ti-Mo Alloys: A Cluster-Model-Embedded First-Principles Study
Xiaoyun Li1, Qixiang Zhang1, Yulong Zhao1
1School of Materials Science and Engineering, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), Dalian University of Technology, Dalian 116024, China.
Materials (Basel, Switzerland)
|August 13, 2026
Summary
First-principles calculations reveal that higher molybdenum content enhances body-centered cubic structural stability in Ti-Mo alloys. This stability influences deformation mechanisms, favoring dislocation slip over phase transformation in high-molybdenum alloys.
Area of Science:
- Materials Science
- Computational Materials Science
- Alloy Design
Background:
- Titanium-molybdenum (Ti-Mo) alloys are crucial in various applications due to their unique mechanical properties.
- Understanding the relationship between structural stability and deformation mechanisms is key to optimizing alloy performance.
Purpose of the Study:
- To investigate the link between body-centered cubic (BCC) structural stability and deformation mechanisms in Ti-Mo alloys.
- To determine how molybdenum content affects BCC stability and the resulting mechanical behavior.
Main Methods:
- Employed first-principles (FP) calculations using a cluster model embedded within a BCC supercell.
- Calculated formation energies (Ef) and binding energies (Eb) for different Mo concentrations (2.3–12.5 at. %).
- Analyzed shear moduli and their relationship to phase transformations and dislocation slip.
Main Results:
- BCC structural stability increases with higher molybdenum content.
- Ti-12.5Mo alloy favors a single β phase, exhibiting high shear modulus (36 GPa) that suppresses α″ transformation and promotes dislocation slip.
- Metastable Ti-4.7Mo shows lattice softening and lower shear moduli, facilitating stress-induced α″ transformation.
Conclusions:
- The shear modulus effectively links BCC structural stability to deformation behavior in Ti-Mo alloys.
- Molybdenum content is a critical factor in controlling the mechanical response of Ti-Mo alloys.
- FP calculations provide valuable insights for designing Ti-Mo alloys with desired properties.
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