Molecular Dynamics Simulations of PtTi High-Temperature Shape Memory Alloys Based on a Modified Embedded-Atom Method...

Area of Science:

• Materials Science
• Computational Materials Science
• Condensed Matter Physics

Background:

• Equiatomic Platinum-Titanium (PtTi) exhibits shape memory alloy properties with potential for high-temperature applications.
• Accurate interatomic potentials are crucial for simulating material behavior and predicting properties.

Purpose of the Study:

• To develop a robust interatomic potential for PtTi alloys.
• To investigate the temperature- and stress-induced martensitic transformations in PtTi using molecular dynamics simulations.

Main Methods:

• Development of a modified embedded-atom model (MEAM) based interatomic potential for PtTi.
• Large-scale molecular dynamics (MD) simulations of single crystalline and nanocrystalline PtTi configurations.
• Analysis of phase transformations between austenite (B2) and martensite (B19) phases.

Main Results:

• The developed PtTi potential accurately reproduces experimental physical properties of equiatomic PtTi and related alloys.
• Simulations demonstrate reversible, temperature- and stress-induced martensitic transformations in PtTi.
• Anisotropy, constraint, and grain orientation significantly influence transformation temperature, mechanical response, and microstructure.

Conclusions:

• The new MEAM-based PtTi potential is suitable for large-scale MD simulations of shape memory phenomena.
• The study highlights the critical role of microstructural features in tailoring PtTi shape memory alloy performance.
• This work provides a foundation for designing advanced PtTi-based high-temperature shape memory alloys.