Publication detail

Microstructural stability and precipitate evolution of thermally treated 7075 aluminum alloy fabricated by cold spray

JUDAS, J. ZAPLETAL, J. ADAM, O. ŘEHOŘEK, L. JAN, V.

Original Title

Microstructural stability and precipitate evolution of thermally treated 7075 aluminum alloy fabricated by cold spray

Type

journal article in Web of Science

Language

English

Original Abstract

In this work, the effects of post-deposition heat treatment on microstructural stability of cold sprayed AA7075 aluminum coatings were thoroughly characterized. The as-atomized powder and annealed coatings were investigated using scanning electron microscopy, electron back-scattered diffraction, and microhardness measurements. Scanning transmission electron microscopy was further employed to evaluate grain/subgrain structure near the particle interface region. Precipitation in the coating was studied through differential scanning calorimetry and X-ray diffraction. The feedstock powder revealed dendritic/cellular-like structure accompanied by microsegregations of the main alloying elements at dendrite boundaries. The high-pressure Cold Spray process led to formation of lamellar subgrains and UFG grains via dynamic recovery/recrystallization mechanisms. GP zones present in the AA7075 powder continuously reprecipitated into more stable η´/η phases owing to propellant gas heating and extensive plastic strains induced during cold spraying. The applied annealing resulted in progressive softening of the AA7075 coatings and gradual transformation of LAGBs into HAGBs. The solute-rich grain boundary network observed in powder microstructure was fully retained after CS deposition but decomposed into coarse η and S precipitates upon high-temperature annealing. The CS AA7075 coating showed decent thermal stability up to 300 °C and rapid grain growth at 400 °C. The relationship between precipitate size and thermal stability was further discussed in terms of the Zener pinning theory.

Keywords

Cold spray, aluminum alloy 7075, microstructure, DSC

Authors

JUDAS, J.; ZAPLETAL, J.; ADAM, O.; ŘEHOŘEK, L.; JAN, V.

Released

1. 8. 2024

Publisher

ELSEVIER

Location

NEW YORK

ISBN

1873-4189

Periodical

MATERIALS CHARACTERIZATION

Year of study

216

Number

114259

State

United States of America

Pages from

114259

Pages to

114259

Pages count

12

URL

https://www.sciencedirect.com/science/article/pii/S1044580324006405

BibTex

@article{BUT189497,
  author="Jakub {Judas} and Josef {Zapletal} and Ondřej {Adam} and Lukáš {Řehořek} and Vít {Jan}",
  title="Microstructural stability and precipitate evolution of thermally treated 7075 aluminum alloy fabricated by cold spray",
  journal="MATERIALS CHARACTERIZATION",
  year="2024",
  volume="216",
  number="114259",
  pages="114259--114259",
  doi="10.1016/j.matchar.2024.114259",
  issn="1873-4189",
  url="https://www.sciencedirect.com/science/article/pii/S1044580324006405"
}