Modeling the atomic structure of an amorphous Co57Ti43 alloy produced by mechanical alloying using RMC simulations

The local atomic order of an amorphous Co57Ti43 alloy produced by Mechanical Alloying was studied by synchrotron x-ray diffraction and modeled through reverse Monte Carlo (RMC) simulations of its x-ray total structure factor. Average coordination numbers and average interatomic distances between first neighbors were calculated using the gij(r)gij(r) functions obtained from the RMC simulations. The values found were compared to data obtained recently using the Extended X-ray Absorption Fine Structure (EXAFS) technique. The results obtained from the simulations corroborated the shortening in the Co–Ti average interatomic distance indicated by the EXAFS analyses, and average coordination numbers and average interatomic distances obtained from both methods agree with each other within error bars, except for the Ti–Ti average interatomic distance. In addition, the bond-angle distribution functions Θi−j−k(cosθ)Θi−j−k(cosθ) were obtained from the simulations and compared to the Θi−j−k(cosθ)Θi−j−k(cosθ) functions obtained for an amorphous Ni60Ti40 alloy.