Download file (3.87 MB)
Download as zip (3.29 MB)

Collection

Citation

Description:

Hybrid physical vapour deposition (PVD) combined with atomic layer deposition (ALD) enables the fabrication of metal/ceramic AlNi/AlO(H) nanolaminates with high room-temperature strength, controlled architecture, and promising functional performance, yet their thermal stability remains unresolved. Here, we establish design principles for thermally robust Al-based nanocomposites by systematically assessing their thermal instability through correlated synchrotron X-ray diffraction, high-resolution microscopy, atom probe tomography, and nanoindentation following vacuum annealing between 160◦C and 600◦C.Angle-resolved X-ray diffraction (XRD) reveals Al crystallite evolution while high-resolution microscopy unravels further instability mechanisms: At homologous temperature T hom ≈ 0.52 (∼210◦C), Ni segregation to Al grain boundaries competes with Al 3 Ni formation. Hydroxylated ALD-AlOxHy interlayers become mobile, driving swelling and oxidation of adjacent Al. At T hom ≈0.77 (∼450◦C), κ-Al2O3 crystallises, followed by interlayer rupture, while at T hom ≈ 0.94 (∼600◦C) the nanolaminate architecture collapses into a coarsened Al(Ni) matrix with dispersed Al2O3 inclusions. These coupled transformations progressively reduce hardness, transitioning from confined layer slip to matrix–inclusion-dominated deformation. Beyond elucidating degradation mechanisms, this work shows how hydrogen-mediated interface dynamics and the dual role of alloyed-Ni limit the thermal and mechanical stability, precisely identifying the onset temperatures, and providing a pathway to robust Al-based PVD/ALD nanocomposites.

Rights:

• Creative Commons BY Attribution 4.0 International
  

Keyword: hybrid PVD / ALD, nanocrystalline Al, nanoindentation, phase transformation, thermal stability

Date published: 2026-08-22

Publisher: Wiley

Journal:

• Small (ISSN: 16136810) e75393

Funding:

• Swiss National Science Foundation Z00P2_202089
• Innosuisse - Schweizerische Agentur für Innovationsförderung 42220.1 IP‐ENG
• Deutsche Forschungsgemeinschaft 409476157
• JSPS, Japan Society for the Promotion of Science 24K23036

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.1002/smll.75393

Related item:

Other identifier(s):

Contact agent:

Updated at: 2026-09-01 16:50:20 +0900

Published on MDR: 2026-09-02 12:26:13 +0900