Skip to Main content Skip to Navigation
Journal articles

Room temperature plasticity and phase transformation of nanometer-sized transition alumina nanoparticles under pressure

Abstract : A powder of transition alumina nanoparticles (including γ and a so-called δ-type) is compacted at room temperature in a diamond anvil cell (DAC) under pressures ranging from 5 GPa to 20 GPa. Characterization carried out on thin foils prepared by focused ion beam (FIB), from the compacted powder, unambiguously reveals plasticity. High resolution transmission electron microscopy (HRTEM) and electron diffraction also evidence phase transformation of nanoparticles under high pressure and nanoparticles show faceting parallel to the loading direction with a preferential crystallographic orientation of the facets corresponding to {220} planes of γ−Al2O3. It can also be deduced, from the comparison between the DAC experiments and in situ TEM nano-compression tests on single particles performed in a preceding work, that plasticity is driven by slip bands corresponding to {111} slip planes, common for a spinel structure, such as, for instance, γ−Al2O3. We also demonstrate that at ambient temperature the transition alumina phase is also prone to structural change under high pressures with the following sequence γ-Al2O3 → δ* Al2O3, these two phases coexisting, sometimes, in the same nanoparticle after compaction. Plasticity at room temperature in alumina nanoparticles and the subsequent phase transformation under pressure may have strong impacts on the process of alumina nanostructured ceramics.
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-01757849
Contributor : Lucile Joly-Pottuz <>
Submitted on : Monday, May 3, 2021 - 7:12:08 PM
Last modification on : Friday, June 11, 2021 - 1:00:04 PM

File

ISSA2018.pdf
Files produced by the author(s)

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

I. Issa, Lucile Joly-Pottuz, Julien Réthoré, C. Esnouf, Thierry Douillard, et al.. Room temperature plasticity and phase transformation of nanometer-sized transition alumina nanoparticles under pressure. Acta Materialia, Elsevier, 2018, 150, pp.308-316. ⟨10.1016/j.actamat.2018.03.023⟩. ⟨hal-01757849⟩

Share

Metrics

Record views

401

Files downloads

58