Structural and microstructural properties of nanocrystalline Cu-Fe-Ni powders produced by mechanical alloying

A nanostructured disordered copper-iron-nickel alloy having the (Cu60Fe40)(70)Ni-30 composition was prepared through the mechanical alloying of the elemental powders in a high-energy ball mill under an argon atmosphere. The structural and morphological evolutions during mechanical alloying were investigated by X-ray diffraction and scanning electron microscopy. The patterns obtained were analyzed using the MAUD program. The transformation of the phase depended on the alloying time. The final product of the mechanical alloying process was nanocrystalline double-phase FCC-Cu(Fe,Ni) and BCC-Fe(Ni) solid solutions with a mean crystallite size in the range of few nanometers. The dislocation densities were found to be 6 x 10(15) m(-2), and the strain hardening caused by high-energy mechanical alloying was consistent with the concept of dislocations. (C) 2014 Elsevier B.V. All rights reserved.