Hardening and thermal stability of nanocrystalline AlMg4.8 powder

Hardening and thermal stability of a nanocrystalline CoCrFeNiMnTi0.1 high-entropy alloy processed by high- pressure torsion

A CoCrFeNiMnTi0.1 high-entropy alloy (HEA) was subjected to high-pressure torsion (HPT) processing under 6.0 GPa pressure up to 10 turns. XRD results reveal that the initial and HPT-processed microstructures consist of a single fcc phase and there is no evidence for creating a new phase and the occurrence of a phase transformation during HPT processing. It is shown that there is a gradual evolu...

Synthesis and thermal stability of nanocrystalline Mg-6Al-1Zn-1Si alloy prepared via mechanical alloying

Thermal stability and the kinetics of the grain growth of nano-crystalline Mg-6Al-1Zn-1Si alloy prepared via mechanical alloying (MA) were investigated. It started with elemental powders, using a variety of analytical techniques including differential scanning calorimetry (DSC), X-ray diffraction method (XRD), and scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (E...

Cyclic strain hardening of nanocrystalline nickel

We demonstrate cyclic strain hardening and frequency-dependent fatigue life in electrodeposited nanocrystalline Ni subjected to tension–tension cyclic deformation. These observations are rationalized through mechanistic arguments based on the exhaustion of dislocation sources in the early stages of cyclic loading and on the domination of diffusive processes during later stages. 2005 Acta Materi...

Strong strain hardening in nanocrystalline nickel.

Low strain hardening has hitherto been considered an intrinsic behavior for most nanocrystalline (NC) metals, due to their perceived inability to accumulate dislocations. In this Letter, we show strong strain hardening in NC nickel with a grain size of approximately 20 nm under large plastic strains. Contrary to common belief, we have observed significant dislocation accumulation in the grain i...

Ionic conductivity and thermal stability of magnetron-sputtered nanocrystalline yttria- stabilized zirconia