The short-range-order of mechanically alloyed amorphous Ni-Zr. A comparison of experiment and simulation

Amorphous NixZr1-x powders were prepared by mechanical alloying in the composition range 0.2 equal or smaller than x equal or smaller than 0.7. Total atomic pair distribution functions G(r) and total radial distribution functions RDF(r) were derived from X-ray measurements. The atomic structure of the amorphous alloy was computer simulated by a mofified dense random packing of hard spheres (DRPHS) which allows an adjustable overlap of unequal spheres. The calculated packings were relaxed by a Morse potential and the total atomic pair distribution functions were computed taking into account the different X-ray visibilities of Ni and Zr. There is good agreement between experimentally determined and calculated short-range-order in the whole homogeneity range of the amorphous phase using next neighbour distances rNiNi=2.48 A, rZrZr=3.10 A and rNizr=2.65.