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Influence of Mn on the precipitates in 6082 aluminum alloy

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Cui Zhenjie
Cui Zhenjie
Cui Zhenjie
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Jiang Haichang
Jiang Haichang
Jiang Haichang
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Zhang Duo
Zhang Duo
Zhang Duo
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Dong Qijuan
Dong Qijuan
Dong Qijuan
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Abstract and Figures

The study systematically examined how Mn impacts the precipitates and mechanical properties of 6082 aluminum alloy during the peak state of artificial aging following various natural aging durations, elucidating the underlying mechanisms. It is found that α-Al(Mn,Fe)Si precipitated during homogenization is less in amount in the alloy with lower Mn content, resulting in the less consumption of Si and a lower real Mg/Si ratio to create a relatively Si-rich environment in matrix. The Si-rich environment promotes the nucleation of the precipitates, so that the low Mn alloy precipitates more and finer precipitates in the artificial aging process, and has higher strength than the high Mn alloy. Additionally, it is also found that with the increase of natural aging time, the precipitates of 6082 aluminum alloy are significantly coarsening, and the alloy with lower Mn content can better resist the coarsening process of the precipitates, so that the strength of the alloy decreases more slowly than that of higher Mn alloys, and the negative effects of natural aging are lighter.
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Vol:.(1234567890)
hps://doi.org/10.1007/s10853-023-09291-9
J Mater Sci (2024) 59:9734–9748
Lightweight Materials
Inuence ofMn ontheprecipitates in6082
aluminum alloy
CuiZhenjie1,* , JiangHaichang2, ZhangDuo2, DongQijuan1, PaiJunjun1,and JiaLuanluan1
1 Shandong Key Laboratory ofAdvanced Aluminium Materials andTechnology, Binzhou Institute ofTechnology, Binzhou256600,
China
2 CAS Key Laboratory ofNuclear Materials andSafety Assessment, Institute ofMetal Research, Chinese Academy ofScience,
Shenyang110016, China
ABSTRACT
The study systematically examined how Mn impacts the precipitates and mechan-
ical properties of 6082 aluminum alloy during the peak state of articial aging
following various natural aging durations, elucidating the underlying mecha-
nisms. It is found that α-Al(Mn,Fe)Si precipitated during homogenization is less
in amount in the alloy with lower Mn content, resulting in the less consumption
of Si and a lower real Mg/Si ratio to create a relatively Si-rich environment in
matrix. The Si-rich environment promotes the nucleation of the precipitates, so
that the low Mn alloy precipitates more and ner precipitates in the articial
aging process, and has higher strength than the high Mn alloy. Additionally, it
is also found that with the increase of natural aging time, the precipitates of 6082
aluminum alloy are signicantly coarsening, and the alloy with lower Mn content
can beer resist the coarsening process of the precipitates, so that the strength of
the alloy decreases more slowly than that of higher Mn alloys, and the negative
eects of natural aging are lighter.
Introduction
6xxx aluminum alloy belongs to heat-treatable rein-
forced aluminum alloy, which is widely used in trans-
portation (automotive, railway), construction and
consumer goods industries due to its high specic
strength, excellent formability, and good weldability
[1–3]. The strength of 6xxx aluminum alloy is achieved
through articial aging (AA) after solution heat treat-
ment. The precipitation sequence of the precipitates
is as follows: supersaturated solid solution → solute
clusters → GP zones → β’’(Mg5Si6) → β’(Mg9Si5) → β(
Mg2Si) [4–7]. Generally, during the actual production
process, the alloy unavoidably undergoes a period of
natural aging (NA) at room temperature before arti-
cial aging. Natural aging can have negative eect, lead-
ing to a decrease in the mechanical properties of the
alloy during subsequent articial aging [8, 9].
In the past several decades, researchers both domes-
tically and internationally have conducted extensive
Received: 10 October 2023
Accepted: 17 December 2023
Published online:
14 January 2024
© The Author(s), under
exclusive licence to Springer
Science+Business Media, LLC,
part of Springer Nature, 2024
Handling Editor: Naiqin Zhao.
Address correspondence to E-mail: cuizhenjie@wqucas.com
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Among commonly used aluminum alloys, the 3000 series is notable for its lightweight nature, high mechanical strength, and excellent formability [1]. Key alloying elements such as Fe, Mn, and Si play critical roles in enhancing these properties: Fe prevents mold sticking during die casting [2], Si improves liquid phase fluidity [3,4], and Mn stabilizes intermetallic phases [5,6], thereby improving mechanical properties. However, choosing the right composition of these elements is crucial, as exceeding their weight fractions can lead to the formation of brittle intermetallic compounds [7], adversely affecting mechanical performance. ...
... The COST-507 database [33] includes models for α-AlMnSi and β-AlMnSi, incorporating Fe solubility changes within the Mn sub-lattice [28]. Proposed chemical compositions, such as (Al 16 (Fe, Mn) 4 Si 1 (Al, Si) 2 ) for α-AlMnSi and (Al 15 Si 1 (Al, Si) 4 (Fe, Mn) 6 ) for β-AlMnSi, provide improved phase descriptions but fail to fully capture order-disorder transitions or solubility variations [39]. Table 1 summarizes key equilibrium phases in the quaternary system, listing optimized parameters of the β-AlMnSi phase and corresponding experimental and calculated data [28]. ...
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