Diffusion Studies of Structurally Amorphous Metal Foils Using Molecular Dynamics Simulation
Jordan Campbell, Olivia Graeve
Materials Science and Engineering program, University of California San Diego, La Jolla, California, USA
Structurally amorphous metals, also known as bulk metallic glasses or amorphous metallic alloys, are materials that have been undercooled rapidly enough to prevent the typical crystal nucleation that these alloys usually undergo. Structurally amorphous metals have demonstrated high strength and hardness, in comparison to their crystalline alloy counterparts, which is why they have seen increased technological interest in recent years. Most spectroscopic methods do not allow study of the evolution of these materials, but molecular dynamics has emerged as a powerful tool for the study of such systems. This endeavor has been limited to the study of low component (< 3 element) alloys due to availability of accurate many - body potentials for structurally amorphous metal alloys. To overcome this, we describe initial attempts to use embedded atom method potentials (EAM) and Morse potentials, combined in LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator), to create meaningful pseudopotentials for the study of systems such as these ones. For preliminary results, common neighbor analysis and yield strengths were used to show that a combination of embedded atom potentials and Morse Potentials produce sufficient potentials for modeling metallic glasses with three components, in comparison to just embedded atom potentials, suggesting that similar techniques could be used to make pseudopotentials for structurally amorphous metals with more than three components.