Effect of Inherent Mg/Ti Interface Structure on Element Segregation and Bonding Behavior: An Ab Initio Study
Xiaodong Zhu1, Kaiming Cheng1, Jin Wang1
1Shandong Provincial Key Laboratory of High Strength Lightweight Metallic Materials, Advanced Materials Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China.
Materials (Basel, Switzerland)
|January 25, 2025
Summary
This study reveals how magnesium (Mg) and titanium (Ti) atoms arrange at their interface in composites. Rare-earth elements like Gadolinium (Gd) and Yttrium (Y) improve bonding and mechanical properties.
Area of Science:
- Materials Science
- Computational Materials Science
Background:
- Magnesium-matrix composites reinforced with titanium particles are crucial for advanced applications.
- Understanding the atomic structure at the Mg/Ti interface is key to optimizing composite properties.
Purpose of the Study:
- Investigate the inherent Mg/Ti interface structure formed during solidification.
- Analyze the role of rare-earth elements (Gd, Y) in interface modification and mechanical enhancement.
Main Methods:
- Ab initio molecular dynamics (AIMD) simulations.
- Density functional theory (DFT) calculations.
- Climbing image nudged elastic band (CI-NEB) method for diffusion analysis.
Main Results:
- Identified an orientation relationship (0001Mg//0001Ti) with an 8% lattice mismatch.
- Observed Mg plane rotation and vacancy formation to accommodate mismatch.
- Demonstrated strong segregation of Gd and Y to the Mg/Ti interface.
- Calculated enhanced interfacial adhesion due to rare-earth segregation.
Conclusions:
- The inherent Mg/Ti interface structure facilitates specific atomic arrangements and rare-earth element segregation.
- Segregation of Gd and Y significantly enhances interfacial adhesion, benefiting the mechanical properties of Ti particle-reinforced Mg composites.
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