Effectively one-dimensional phase diagram of CuZr liquids and glasses

This paper presents computer simulations of CuxZr100−x (x = 36, 50, 64) in the liquid and glass phases. The
simulations are based on the effective-medium theory potentials. We find good invariance of both structure
and dynamics in reduced units along the isomorphs of the systems. The state points studied involve a density
variation of almost a factor of 2 and temperatures going from 1500 K to above 4000 K for the liquids and
from 500 K to above 1500 K for the glasses. For comparison, results are presented also for similar temperature
variations along isochores, showing little invariance. In general for a binary system the phase diagram has three
axes: composition, temperature, and pressure (or density). When isomorphs are present, there are effectively
only two axes, and for a fixed composition there is just one. We conclude that the liquid and glass parts
of the thermodynamic phase diagram of this metallic glass former at a fixed composition are effectively
one-dimensional in the sense that many physical properties are invariant along the same curves, implying that in
order to investigate the phase diagram, it is only necessary to go across these curves.