Elastic properties of Fe95-yNb2Mo2Cu1Siy-xBx (x=5-8, y=20-26) at % amorphous alloys

Amorphous materials exhibit complex atomic structures characterized by the absence of long-range order, in contrast to the well-defined periodicity of crystalline materials. This structural complexity is pronounced in FeMCuSiB (M = Nb, Mo, W and Ta), incorporating elements with varying atomic radii and valencies. The Young’s modulus, of structures generated using traditional methods, such as melt-quenching and random packing disagree with experiments. In this study, we employ hybrid methods that involve randomly packing elements without overlap, followed by room-temperature thermalization using Ab-initio Molecular Dynamics simulations. The evaluated from these structures aligns well with values measured using Dynamic Mechanical Analysis. Additionally, we find that other elastic moduli determined using these structures are consistent with measurements. We attribute the improved accuracy to a better representation of the structure and the application of energy-strain relationships, rather than stress-strain relationships. Our methodology facilitates the design of these alloys with desired mechanical properties.