STRUCTURE OF THE METALLIC-GLASS DY44NI56 BY COMPUTER-SIMULATION OF THE EXPERIMENTAL PAIR CORRELATION-FUNCTIONS

The partial pair correlation functions of amorphous Dy44Ni56 as obtain ed experimentally in an earlier paper are simulated by a cluster relax ation procedure. Reasonable agreement with the experimental functions is obtained when non-additive pair potentials with preference for Dy-N i atomic pairs are applied. The refinement of the atomic cluster by us ing the reverse Monte Carlo method yields perfect agreement. The chara cterization of the chemical short range order depends on the definitio n of an appropriate hypothetic statistical reference system since the influence of the size effect is essential. The structure of amorphous Dy44Ni56 is compared with representative examples from different group s of metallic glasses, such as Nb-Ni, Ni-B and Ni-P. Some structural f eatures point to a relationship with the related crystalline phase DyN i, whereas other features show that the different types of metallic gl ass have certain structural principles in common. The structural model s reveal rather broad distributions of the local structural properties and show that amorphous Dy44Ni56 is not built as an assembly of defin ed structural units.