Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys

This study examines the impact of alloy composition and overageing heat treatments on mechanical properties and corrosion behaviour of aluminium crossover alloys, with a particular focus on the AlMgZn(Cu,Ag) system. Mechanical properties were evaluated through hardness and tensile testing, while cor...

Full description

Saved in:
Bibliographic Details
Main Authors: P.D. Willenshofer, L. Pezzato, I. Weißensteiner, T. Bortolussi, M.A. Tunes, I. Calliari, S. Pogatscher
Format: Article
Language:English
Published: Elsevier 2025-06-01
Series:Materials & Design
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0264127525004666
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849330900878229504
author P.D. Willenshofer
L. Pezzato
I. Weißensteiner
T. Bortolussi
M.A. Tunes
I. Calliari
S. Pogatscher
author_facet P.D. Willenshofer
L. Pezzato
I. Weißensteiner
T. Bortolussi
M.A. Tunes
I. Calliari
S. Pogatscher
author_sort P.D. Willenshofer
collection DOAJ
description This study examines the impact of alloy composition and overageing heat treatments on mechanical properties and corrosion behaviour of aluminium crossover alloys, with a particular focus on the AlMgZn(Cu,Ag) system. Mechanical properties were evaluated through hardness and tensile testing, while corrosion resistance was examined in a solution of NaCl through mass loss tests, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). Mass loss tests indicated that addition of noble elements (Cu,Ag) has an adverse effect on corrosion resistance, which was further corroborated by PDP and EIS. These observations are not in accordance with effects commonly observed in classical 5xxx and 7xxx alloys, from which the alloy originates. To establish a correlation between mechanical and corrosion properties and the microstructure, scanning and transmission electron microscopy (SEM,S/TEM) were employed. We resort to characterization techniques to investigate the influence of grain size, texture, grain boundary precipitate, precipitate-free zone, and bulk precipitate characteristics on the observed corrosion response. The results demonstrate that the presence of Cu and Ag primarily weakens the protective oxide layer and creates a galvanic coupling, resulting in increased corrosion currents between matrix and precipitates. Double-step overageing primarily causes precipitate coarsening. While the addition of Cu and Ag can enhance mechanical properties by refining strengthening precipitates, their addition deteriorate corrosion resistance in novel 5xxx/7xxx aluminium crossover alloys.
format Article
id doaj-art-ce6bb04282b74683a3c898c654f994f2
institution Kabale University
issn 0264-1275
language English
publishDate 2025-06-01
publisher Elsevier
record_format Article
series Materials & Design
spelling doaj-art-ce6bb04282b74683a3c898c654f994f22025-08-20T03:46:46ZengElsevierMaterials & Design0264-12752025-06-0125411404610.1016/j.matdes.2025.114046Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloysP.D. Willenshofer0L. Pezzato1I. Weißensteiner2T. Bortolussi3M.A. Tunes4I. Calliari5S. Pogatscher6Chair of Non-Ferrous Metallurgy, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, Austria; Corresponding author.Institute of Condensed Matter Chemistry and Energy Technologies (ICMATE), National Research Council of Italy, C.so Stati Uniti 4, 35127 Padova, ItalyChristian Doppler Laboratory for Advanced Aluminum Alloys, Franz Josef Strasse 18, 8700 Leoben, Austria; Chair of Non-Ferrous Metallurgy, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, AustriaDepartment of Industrial Engineering, University of Padova, Via Marzolo 9, 35131 Padova, Italy; Chair of Non-Ferrous Metallurgy, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, AustriaChair of Non-Ferrous Metallurgy, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, AustriaDepartment of Industrial Engineering, University of Padova, Via Marzolo 9, 35131 Padova, ItalyChair of Non-Ferrous Metallurgy, Montanuniversität Leoben, Franz Josef Strasse 18, 8700 Leoben, AustriaThis study examines the impact of alloy composition and overageing heat treatments on mechanical properties and corrosion behaviour of aluminium crossover alloys, with a particular focus on the AlMgZn(Cu,Ag) system. Mechanical properties were evaluated through hardness and tensile testing, while corrosion resistance was examined in a solution of NaCl through mass loss tests, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). Mass loss tests indicated that addition of noble elements (Cu,Ag) has an adverse effect on corrosion resistance, which was further corroborated by PDP and EIS. These observations are not in accordance with effects commonly observed in classical 5xxx and 7xxx alloys, from which the alloy originates. To establish a correlation between mechanical and corrosion properties and the microstructure, scanning and transmission electron microscopy (SEM,S/TEM) were employed. We resort to characterization techniques to investigate the influence of grain size, texture, grain boundary precipitate, precipitate-free zone, and bulk precipitate characteristics on the observed corrosion response. The results demonstrate that the presence of Cu and Ag primarily weakens the protective oxide layer and creates a galvanic coupling, resulting in increased corrosion currents between matrix and precipitates. Double-step overageing primarily causes precipitate coarsening. While the addition of Cu and Ag can enhance mechanical properties by refining strengthening precipitates, their addition deteriorate corrosion resistance in novel 5xxx/7xxx aluminium crossover alloys.http://www.sciencedirect.com/science/article/pii/S0264127525004666Corrosion(Scanning) transmission electron microscopyAluminium crossover alloys
spellingShingle P.D. Willenshofer
L. Pezzato
I. Weißensteiner
T. Bortolussi
M.A. Tunes
I. Calliari
S. Pogatscher
Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
Materials & Design
Corrosion
(Scanning) transmission electron microscopy
Aluminium crossover alloys
title Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
title_full Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
title_fullStr Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
title_full_unstemmed Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
title_short Influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
title_sort influence of alloy chemistry and overaging on mechanical properties and corrosion resistance in aluminium crossover alloys
topic Corrosion
(Scanning) transmission electron microscopy
Aluminium crossover alloys
url http://www.sciencedirect.com/science/article/pii/S0264127525004666
work_keys_str_mv AT pdwillenshofer influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys
AT lpezzato influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys
AT iweißensteiner influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys
AT tbortolussi influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys
AT matunes influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys
AT icalliari influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys
AT spogatscher influenceofalloychemistryandoveragingonmechanicalpropertiesandcorrosionresistanceinaluminiumcrossoveralloys