Abstract
Morphological, structural, and microstructural properties of nanocrystalline Fe50Co40Ni10 alloy prepared by high-energy planetary ball milling were studied by scanning electron microscopy and X-ray diffraction. The morphological observations reveal a progressive refinement of particle size with milling time. Longer milling leads to a narrow particle size distribution with irregular shape. The evolution of phase composition, phase transformation, and structural and microstructural parameters is examined as function of milling time (0-48 h) by using the Rietveld refinements of X-ray diffraction patterns. A new solid solution phase with a bcc-type structure was achieved within the Fe matrix, with a mean crystallite size of 8.17 nm (+/- 0.02) and a lattice strain% of 0.56% (+/- 0.01). The formation of the nanocrystalline alloy was attributed to the severe plastic deformations introduced by mechanical alloying and the high diffusivity between the constituting elements. Indeed, high dislocation density and grain boundary were generated resulting in the distortion of the crystal lattice accompanied by a significant reduction in the lattice parameter from 0.28663 nm (+/- 0.00001) up to 0.28557 nm (+/- 0.00007).
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