Short-range and medium-range order in liquid AuGe alloys

Abstract

Molten gold-rich alloys have been investigated using X-ray wide-angle scattering. At temperatures below the melting points of the two components, a distinct prepeak has been found around a scattering vector magnitude of 1.35 Å−1. For the liquid eutectic alloy Au72Ge28 (melting point: 634 K), this prepeak decreases its intensity with increasing temperature but is clearly existent up to temperatures of 1273 K. This behaviour indicates stable medium-range order up to nearly 650 K above the melting point. It is concluded that the alloys contain associated regions, possibly bearing some resemblance to the structure of metastable crystalline alloys. © 1995, All rights reserved.