Supersaturated metastable Ag-Ni solid solutions formed by ion beam mixing

Abstract

Extension of terminal solid solubilities has been achieved by ion beam mixing in the almost completely immiscible Ag-Ni system. Multi-layered samples of thin deposited Ag-Ni films of various compositions were bombarded with energetic Xe ions at temperatures from −190 to 250 °C. Supersaturated Ag- and Ni-rich fcc solid solutions were obtained, as indicated by x-ray and electron diffraction. Analyses of lattice parameters showed that the solubility range for the metastable solid solutions produced by low-temperature bombardment was wider than for those formed at high temperature. Maximum solubilities were determined to be 4.5 at. % Ni in Ag and 16 at. % Ag in Ni if one assumes the ion-induced fcc phases to be ideal solid solutions. The effects of implantation temperature on the formation of metastable phases are discussed.