Structural characterization of mechanically alloyed nanocrystalline Cu-Fe: Strain broadening due to dislocations

Abstract

Abstract. Nanocrystalline Cu(Fe) solid solution was successfully synthesized by using high-energy mechanical milling. The structural and morphological changes during mechanical milling were investigated by X-ray diffraction and scanning electron microscopy. The patterns so obtained were analyzed using the X'Pert High Score Plus program. The final product of the mechanical alloying process was nanocrystalline FCC Cu(Fe) solid solution with a mean crystallite size in the range of few nanometers. The final microstructure, especially the high levels of lattice strains was explained by the presence of dislocations, with a dislocation density of about 7.4×10 16 m −2 . The identified steady-state saturation values of these parameters can be related to accumulate strain hardening of the powder material during longer milling times.

Magnetic phase diagram of superantiferromagnetic TbCu2nanoparticles

“…Regarding the size variation, the milling process results in nanometric particles, as discussed in previous works [12,21]. The D(t) and ( ) η t behaviors are similar to those observed in other 4f- [18,21] and 3d-Cu [26] based planetary-milled alloys, and the only most noticeable difference is, as commented on above, the reduced time required to achieve nanometric particle sizes. For example, t = 300 h for D = 14 nm TbAl 2 [21], t = 120 h for D = 21 nm GdAl 2 [18] and t = 20 h for D = 18 nm YbAl 3 [24], while for TbCu 2 only t = 0.5 h was necessary to reduce particle size down to D = 23 nm.…”