Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers
AA2024, a high-strength aluminum wrought alloy, is widely used in the production of aircraft components, for example, frames and stringers. While the alloy is relatively soft and formable in the solution heat treated and quenched state (W temper), rapid onset of natural ageing increases hardness and...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-02-01
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| Series: | Materials & Design |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S0264127523000497 |
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| author | J.A. Österreicher D. Nebeling F. Grabner A. Cerny G.A. Zickler J. Eriksson G. Wikström W. Suppan C.M. Schlögl |
| author_facet | J.A. Österreicher D. Nebeling F. Grabner A. Cerny G.A. Zickler J. Eriksson G. Wikström W. Suppan C.M. Schlögl |
| author_sort | J.A. Österreicher |
| collection | DOAJ |
| description | AA2024, a high-strength aluminum wrought alloy, is widely used in the production of aircraft components, for example, frames and stringers. While the alloy is relatively soft and formable in the solution heat treated and quenched state (W temper), rapid onset of natural ageing increases hardness and decreases ductility within few hours, creating a logistical challenge for the fabrication of frames by roll forming and bending, or other sheet metal forming operations. Here we investigate pre-ageing heat treatments of AA2024 with the aim of creating more stable and formable material conditions. The progression of materials properties after heat treatment is compared to natural ageing by extensive tensile test time series. An inhibition of secondary natural ageing by pre-ageing is demonstrated and a possible microstructural explanation is presented based on transmission electron microscopy and differential scanning calorimetry: S-phase is present in the pre-aged temper, and we suggest that the formation of Mg/Cu-clusters is suppressed. Formability is assessed by forming limit curves and finite element simulation of three-roll-push bending of frame profiles. We found improved processability of the pre-aged temper compared to a one week naturally aged condition: The forming limits are increased, and wrinkling in the bending simulations is reduced. |
| first_indexed | 2024-04-10T05:25:03Z |
| format | Article |
| id | doaj.art-a6b15a11a64343eeb63a1dacca6ab354 |
| institution | Directory Open Access Journal |
| issn | 0264-1275 |
| language | English |
| last_indexed | 2024-04-10T05:25:03Z |
| publishDate | 2023-02-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Materials & Design |
| spelling | doaj.art-a6b15a11a64343eeb63a1dacca6ab3542023-03-08T04:13:37ZengElsevierMaterials & Design0264-12752023-02-01226111634Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempersJ.A. Österreicher0D. Nebeling1F. Grabner2A. Cerny3G.A. Zickler4J. Eriksson5G. Wikström6W. Suppan7C.M. Schlögl8LKR Light Metals Technologies, Austrian Institute of Technology, 5282 Ranshofen, Austria; Corresponding author.Chair of Forming Technology, Institute of Production Technologies, University of Siegen, 57076 Siegen, GermanyLKR Light Metals Technologies, Austrian Institute of Technology, 5282 Ranshofen, AustriaLKR Light Metals Technologies, Austrian Institute of Technology, 5282 Ranshofen, Austria; Department of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, 5020 Salzburg, AustriaDepartment of Chemistry and Physics of Materials, Paris Lodron University of Salzburg, 5020 Salzburg, AustriaOrtic AB, 781 74 Borlänge, SwedenOrtic AB, 781 74 Borlänge, SwedenVoestalpine Metal Forming Division, 4020 Linz, AustriaLKR Light Metals Technologies, Austrian Institute of Technology, 5282 Ranshofen, AustriaAA2024, a high-strength aluminum wrought alloy, is widely used in the production of aircraft components, for example, frames and stringers. While the alloy is relatively soft and formable in the solution heat treated and quenched state (W temper), rapid onset of natural ageing increases hardness and decreases ductility within few hours, creating a logistical challenge for the fabrication of frames by roll forming and bending, or other sheet metal forming operations. Here we investigate pre-ageing heat treatments of AA2024 with the aim of creating more stable and formable material conditions. The progression of materials properties after heat treatment is compared to natural ageing by extensive tensile test time series. An inhibition of secondary natural ageing by pre-ageing is demonstrated and a possible microstructural explanation is presented based on transmission electron microscopy and differential scanning calorimetry: S-phase is present in the pre-aged temper, and we suggest that the formation of Mg/Cu-clusters is suppressed. Formability is assessed by forming limit curves and finite element simulation of three-roll-push bending of frame profiles. We found improved processability of the pre-aged temper compared to a one week naturally aged condition: The forming limits are increased, and wrinkling in the bending simulations is reduced.http://www.sciencedirect.com/science/article/pii/S0264127523000497Roll formingBendingThree-roll-push bendingForming limit curveTransmission electron microscopyCryogenic storage |
| spellingShingle | J.A. Österreicher D. Nebeling F. Grabner A. Cerny G.A. Zickler J. Eriksson G. Wikström W. Suppan C.M. Schlögl Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers Materials & Design Roll forming Bending Three-roll-push bending Forming limit curve Transmission electron microscopy Cryogenic storage |
| title | Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers |
| title_full | Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers |
| title_fullStr | Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers |
| title_full_unstemmed | Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers |
| title_short | Secondary ageing and formability of an Al-Cu-Mg alloy (2024) in W and under-aged tempers |
| title_sort | secondary ageing and formability of an al cu mg alloy 2024 in w and under aged tempers |
| topic | Roll forming Bending Three-roll-push bending Forming limit curve Transmission electron microscopy Cryogenic storage |
| url | http://www.sciencedirect.com/science/article/pii/S0264127523000497 |
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