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Regular version of the site

Article

The effect of thermal history on the atomic structure and mechanical properties of amorphous alloys

Computational Materials Science. 2020. Vol. 174. P. 109477.

The influence of thermal processing on the potential energy, atomic
structure, and mechanical properties of metallic glasses is examined
using molecular dynamics simulations. We study the three-dimensional
binary mixture, which was first relaxed near the glass transition
temperature, and then rapidly cooled deep into the glass phase.  It
was found that glasses prepared at higher annealing temperatures are
relocated to higher energy states and their average glass structure
remains more disordered, as reflected in the shape of the pair
correlation function. The results of mechanical testing demonstrate
that both the shear modulus and yielding peak increase significantly
when the annealing temperature approaches $T_g$ from above.
Moreover, the shear modulus becomes a strong function of strain rate
only for samples equilibrated at sufficiently high temperatures.
Based on the spatial distribution of nonaffine displacements, we
show that the deformation mode changes from brittle to ductile upon
increasing annealing temperature.  These results can be useful for
the design and optimization of the fabrication processes of bulk
glassy alloys with improved plasticity.