Publish in OALib Journal
APC: Only $99
Nanocrystalline Ni(50-x)Ti50Cux(X = 5, 9 wt%) alloys were successfully produced by mechanical alloying. Mechanical activation was performed at different milling times under a high purity argon (99.998 vol%) atmosphere. Phase analysis and structural features of the samples were examined by X-ray diffraction (XRD). Results revealed that NiTiCu (B2) phase was achieved after 600 min of milling. The formation of this phase was mostly related to the critical factors in determining the site replacement of elements in Ni-Ti-Cu ternary system. After 600 min of milling, the average crystallite size and lattice strain of the samples were about 5 - 10 nm and 1.057% - 1.967%, respectively. Evaluation of the full width at half maximum (FWHM) values for all the samples indicated the occurrence of anisotropic line broadening. The determined amounts of crystallinity revealed that the fraction of crystalline phase decreased with increasing weight percentage of copper up to 9% and reached a minimum value after 600 min of milling. The lattice parameters and the unit cell volume of the milled samples were always larger than the standard values. In addition, lattice parameter deviation influenced by the weight percentage of copper. Based on the obtained data, mechanical alloying process can be used for production of nanocrystalline NiTiCu alloys with different structural features.
present manuscript, the authors have systematically investigated the structural
and morphological properties of a series of mechanically alloyed Fe1-xAlx (0.3 ≤ x ≤ 0.6) samples using X-Ray
Diffraction (XRD) and Scanning Electron Microscopy (SEM). All the samples,
after 5 hr of milling, show crystalline structure, irrespective of the
constituent concentration and are textured mainly along (110) direction. In
Fe-rich samples, the formation of an off-stoichiometric Fe3Al phase
is favored and in case of Al-rich samples, both Al-rich phases and clustering
of Al atoms are present. Analysis of line breadths was carried out to get an
insight into the interrelated effects of average crystallite size, and lattice
parameters. The grain size of constituents was decreased to the nanometer range
(between 6 - 8 nm) and the constituents dissolved at the nanograin boundaries.
Similar conclusions were also revealed from the SEM results which show that the
initial shape of particles disappeared completely, and their structure became a
mixture of small and large angularshaped crystallites with different sizes. The
results of this research could be directly employed in the design of
deformation schedules for the industrial processing of Fe-Al alloys.