EXAFS study on amorphous and nanocrystalline M–W (M=Fe,Ni) alloys produced by electrodeposition

Abstract Ductile amorphous and nanocrystalline M–W (M=Fe,Ni) alloys were produced by electrodeposition. Structural studies of these alloys were made by using EXAFS and SAXS methods. The crystal structure of the electrodeposited Ni–W alloy was similar to that of the Ni4W crystal phase. The nearest Ni–Ni distance was determined to be 2.49 A; the Ni–W distance was determined to be 2.50 A. The atomic distances in the nanocrystalline Ni–W alloys increases with the tungsten concentration. The average crystal grain size of the Ni–W alloy was estimated at about 2.5 nm from a Guinier plot of the SAXS spectra. The electrodeposited amorphous Fe–21.6 at.% W alloy has only short range order, and no medium range order.