Pressure effects on local atomic structure of Ni15Co15Al70 metallic glasses

M Kbirou and A Hasnaoui and K Saadouni and M Badawi and M Mazroui, COMPUTATIONAL MATERIALS SCIENCE, 166, 20-29 (2019).

DOI: 10.1016/j.commatsci.2019.04.052

Molecular dynamics simulations are used to study the pressure effects on the local atomic structure of Ni15Co15Al70 metallic glasses. Interatomic interactions are modeled by the semi-empirical embedded atom method. The effects of pressure were systematically investigated through a variety of local structural analysis methods, such as bond angle distribution, structure factor, Voronoi tessellation and total and partial coordination numbers. Via the Went-Abraham parameter, our numerical results show an increase of the glass transition temperature Tg with increasing pressure. In the same context, Voronoi tessellation and coordination number analyses indicate that the local structure of glassy Ni15Co15Al70 is obviously influenced by the applied pressure, and the degree of local fivefold symmetry in the quenched systems decreases when the pressure increases. Lastly, we also investigated other parameters of structural disorder in amorphous alloys Ni15Co15Al70, including the concept of free volume and the atomic-level stresses. Implications of these findings are discussed.

Return to Publications page