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Yucel Birol - One of the best experts on this subject based on the ideXlab platform.
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Impact of pre-ageing on age Hardening Response of twin-belt cast AlMg1SiCu sheet
Journal of Materials Science, 2010Co-Authors: Yucel BirolAbstract:The potential of twin-belt cast (TBC) AlMg1SiCu sheet for structural automotive applications was investigated with a particular emphasis on the impact of pre-ageing on its age Hardening Response. The optimum T6 process for the TBC AlMg1SiCu sheet is identified to be a water-quench from the solution heat treatment at 540 °C and a subsequent ageing treatment at 180 °C. This process gives hardness values as high as 120 HV within several hours when ageing at 180 °C is performed shortly after the solution treatment. The age Hardening capacity is impaired, however, when the sheet is stored at room temperature before the artificial ageing cycle. Pre-ageing at 100 and 140 °C is effective in improving the age Hardening Response of the naturally aged 6061 sheet. Pre-ageing suppresses natural ageing and clustering activities and gives lower T4 yet a much higher T6 hardness.
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Reversion Treatment to Improve Bake Hardening Response of a Twin-Roll Cast 6016 Automotive Sheet
Materials Science Forum, 2007Co-Authors: Yucel BirolAbstract:Heat-treatable Al-Mg-Si aluminum alloys for automotive body panel applications are shipped and formed in T4 temper while still formable and are subsequently given a bake cycle to increase strength by age Hardening while the paint is cured. However, the Hardening Response during the rather short industrial paint-bake is impaired upon natural ageing after the solution treatment. It is thus essential to counteract the adverse effect of natural ageing on bake Hardening. While this is often accomplished by an additional ageing cycle before the paint-bake treatment, reversion treatments ought to be used once substantial natural ageing has first taken place to improve the bake Hardening Response of a twin-roll cast 6016 sheet. The present work was undertaken to improve the paint bake Response of a twin-roll cast 6016 sheet by employing reversion treatments before the paint-bake cycle. Reversion treatments between 200°C and 250°C was effective in improving the bake Hardening Response of the twin-roll cast 6016 sheet which, when processed without reversion, failed to meet in-service strength requirements with a rather poor bake Hardening Response of 35 MPa.
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Restoration of the bake Hardening Response in a naturally aged twin-roll cast AlMgSi automotive sheet
Scripta Materialia, 2006Co-Authors: Yucel BirolAbstract:Abstract Reversion treatments at 225 °C for several minutes were effective in improving the bake Hardening Response of the naturally aged twin-roll cast AlMgSi sheet which, when processed without reversion, failed to meet in-service strength requirements with a rather poor bake Hardening Response.
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Pre-straining to improve the bake Hardening Response of a twin-roll cast Al¿Mg¿Si alloy
Scripta Materialia, 2005Co-Authors: Yucel BirolAbstract:Abstract Twin-roll cast (TRC) Al–Mg–Si sheet samples were pre-strained in tension shortly after the solution treatment. Microhardness, electrical conductivity and differential scanning calorimetry measurements were employed to investigate the effect of a mechanical rather than a thermal treatment on the bake Hardening Response.
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Effect of natural ageing on the performance of pre-ageing to improve bake-Hardening Response of a twin-roll cast Al - Mg - Si alloy
Zeitschrift für Metallkunde, 2005Co-Authors: Yucel BirolAbstract:Abstract Since a room-temperature delay between the solution heat treatment and the paint-bake cycle is unavoidable in industrial practice, it is essential to counteract the adverse effect of natural ageing on the bake-Hardening Response of Al–Mg–Si alloys. This is often accomplished by an additional ageing cycle, referred to as pre-ageing, before the paint-bake treatment. While pre-ageing treatments shortly after the solution treatment are very attractive, long delays prior to pre-ageing produce undesirable effects on the bake-Hardening Response. The best combination of a sufficiently high T8X and a reasonably low T4P yield strength for a twin-roll cast (TRC) Al–Mg–Si alloy is obtained when the sheet is pre-aged for 5 minutes at 180 °C with only a 10-minute delay after the solution treatment. Several hours of natural ageing can be tolerated before the T8X yield strength drops below 200 MPa with a similar heat treatment at 200 °C. Pre-ageing at even higher temperatures must be employed only after substant...
Simon P. Ringer - One of the best experts on this subject based on the ideXlab platform.
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si induced precipitation modification and related age Hardening Response of an al 4mg 1cu 0 5si alloy
Materials Chemistry and Physics, 2017Co-Authors: Gang Sha, J. H. Xia, Yongchang Liu, Simon P. RingerAbstract:Abstract The solid solubility of Si in a quaternary Al–4Mg–1Cu–0.5Si (wt%) alloy has been found to be only about 0.061 at% at 520 °C, and 0.093 at% at 560 °C, less than 1/10 of that in the ternary Al–Mg–Si system. The excess Si in the alloy remains as coarse Mg2Si dispersoids which produce no significant age-Hardening effect. Interestingly, a small change of Si content (from 0.061 at.% to 0.093 at.%) in the solid solution of the alloy has been found to be effective in modifying precipitation microstructure by promoting the formation of fine Guinier–Preston–Bagaryasky (GPB) zones and postponing the formation of the S phase during ageing at 200 °C. Consequently, the quaternary alloy exhibits an enhanced age-Hardening Response during earlier-stage ageing.
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Si-induced precipitation modification and related age-Hardening Response of an Al–4Mg–1Cu–0.5Si alloy
Materials Chemistry and Physics, 2017Co-Authors: Gang Sha, J. H. Xia, Yongchang Liu, Simon P. RingerAbstract:Abstract The solid solubility of Si in a quaternary Al–4Mg–1Cu–0.5Si (wt%) alloy has been found to be only about 0.061 at% at 520 °C, and 0.093 at% at 560 °C, less than 1/10 of that in the ternary Al–Mg–Si system. The excess Si in the alloy remains as coarse Mg2Si dispersoids which produce no significant age-Hardening effect. Interestingly, a small change of Si content (from 0.061 at.% to 0.093 at.%) in the solid solution of the alloy has been found to be effective in modifying precipitation microstructure by promoting the formation of fine Guinier–Preston–Bagaryasky (GPB) zones and postponing the formation of the S phase during ageing at 200 °C. Consequently, the quaternary alloy exhibits an enhanced age-Hardening Response during earlier-stage ageing.
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effect of solution treatment on precipitation and age Hardening Response of an al 4mg 1cu 0 5si 0 4ag wt alloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2014Co-Authors: Gang Sha, J. H. Xia, B. Gun, J. Z. Cui, Xiaotao Liu, Simon P. RingerAbstract:Abstract An increase in solution temperature from 520 °C to 560 °C doubled Si concentration (from 0.06 at% to 0.13 at%) in the solid solution of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy. Consequently, the alloy exhibited an enhanced age-Hardening Response with a peak hardness of 135 HVN, 10% higher than that of the alloy treated at 520 °C. The treatment at 560 °C enabled the formation of more Guinier–Preston–Bagaryasky (GPB) zones rather than the Z-phase during subsequent ageing at 200 °C, and hence produced an enhanced strengthening effect to the alloy.
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Effect of solution treatment on precipitation and age-Hardening Response of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy
Materials Science and Engineering: A, 2014Co-Authors: Gang Sha, J. H. Xia, B. Gun, J. Z. Cui, Xiaotao Liu, Simon P. RingerAbstract:Abstract An increase in solution temperature from 520 °C to 560 °C doubled Si concentration (from 0.06 at% to 0.13 at%) in the solid solution of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy. Consequently, the alloy exhibited an enhanced age-Hardening Response with a peak hardness of 135 HVN, 10% higher than that of the alloy treated at 520 °C. The treatment at 560 °C enabled the formation of more Guinier–Preston–Bagaryasky (GPB) zones rather than the Z-phase during subsequent ageing at 200 °C, and hence produced an enhanced strengthening effect to the alloy.
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enhanced age Hardening Response of al 4mg 1cu wt microalloyed with ag and si
Scripta Materialia, 2013Co-Authors: Ghang Sha, Bulent Gun, J. H. Xia, Xiang Fa Liu, Nick Birbilis, Simon P. RingerAbstract:Microalloying of an Al–4Mg–1Cu alloy (wt.%) with Si and Ag produced an enhanced age-Hardening Response, increasing peak hardness whilst also accelerating precipitation kinetics due to a modified precipitation process. The addition of Si stabilizes Guinier–Preston–Bagaryasky zones and suppresses T-phase formation. In contrast, the alloy modified with Si + Ag featured extensive precipitation of the Z-phase as platelets on matrix {1 1 1} Al planes, whilst S-phase formation was suppressed.
Vahid Fallah - One of the best experts on this subject based on the ideXlab platform.
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effect of solidification cooling rate on kinetics of continuous discontinuous al3 sc zr precipitation and the subsequent age Hardening Response in cold rolled almgsc zr sheets
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2020Co-Authors: Qingshan Dong, Andrew Howells, David James Lloyd, Mark Gallerneault, Vahid FallahAbstract:Abstract We explain the critical effect of casting processing route (i.e., the solidification cooling rate) on the kinetics of Sc–Zr precipitation upon solidification and, subsequently, on the age-Hardening Response of cold-rolled/aged Al–3Mg-0.36Sc-0.14Zr sheets. The evolution mechanisms of various types of Al3(Sc,Zr) precipitates are investigated in the as-cast specimens (fabricated via strip casting vs. mold casting techniques), as well as in the subsequently cold-rolled/aged sheet specimens. The Al3(Sc,Zr) precipitates appeared to have formed upon either discontinuous or continuous precipitation during cooling from solidification temperatures; the former leads to the formation of lamellar Al3(Sc,Zr) cells while the latter results in the formation of spherical precipitates, all of which possessing an L12 crystal structure and a coherent interface with the α-Al matrix. It is shown that slower cooling rates via mold casting lead to the occurrence of both continuous and discontinuous precipitation upon cooling from the solidification temperature. In contrast, higher cooling rates via strip casting results in the apparent prevention of all discontinuous precipitation reactions as well as in the suppression of continuous precipitation. The overall effect is the greater preservation of Sc supersaturation within the α-Al matrix of the as-cast specimens fabricated via strip casting which, subsequently, leads to higher precipitation kinetics and thus higher tensile properties upon age-Hardening of the cold-rolled sheets.
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Effect of solidification cooling rate on kinetics of continuous/discontinuous Al3(Sc,Zr) precipitation and the subsequent age-Hardening Response in cold-rolled AlMgSc(Zr) sheets
Materials Science and Engineering: A, 2020Co-Authors: Qingshan Dong, Andrew Howells, David James Lloyd, Mark Gallerneault, Vahid FallahAbstract:Abstract We explain the critical effect of casting processing route (i.e., the solidification cooling rate) on the kinetics of Sc–Zr precipitation upon solidification and, subsequently, on the age-Hardening Response of cold-rolled/aged Al–3Mg-0.36Sc-0.14Zr sheets. The evolution mechanisms of various types of Al3(Sc,Zr) precipitates are investigated in the as-cast specimens (fabricated via strip casting vs. mold casting techniques), as well as in the subsequently cold-rolled/aged sheet specimens. The Al3(Sc,Zr) precipitates appeared to have formed upon either discontinuous or continuous precipitation during cooling from solidification temperatures; the former leads to the formation of lamellar Al3(Sc,Zr) cells while the latter results in the formation of spherical precipitates, all of which possessing an L12 crystal structure and a coherent interface with the α-Al matrix. It is shown that slower cooling rates via mold casting lead to the occurrence of both continuous and discontinuous precipitation upon cooling from the solidification temperature. In contrast, higher cooling rates via strip casting results in the apparent prevention of all discontinuous precipitation reactions as well as in the suppression of continuous precipitation. The overall effect is the greater preservation of Sc supersaturation within the α-Al matrix of the as-cast specimens fabricated via strip casting which, subsequently, leads to higher precipitation kinetics and thus higher tensile properties upon age-Hardening of the cold-rolled sheets.
Gang Sha - One of the best experts on this subject based on the ideXlab platform.
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si induced precipitation modification and related age Hardening Response of an al 4mg 1cu 0 5si alloy
Materials Chemistry and Physics, 2017Co-Authors: Gang Sha, J. H. Xia, Yongchang Liu, Simon P. RingerAbstract:Abstract The solid solubility of Si in a quaternary Al–4Mg–1Cu–0.5Si (wt%) alloy has been found to be only about 0.061 at% at 520 °C, and 0.093 at% at 560 °C, less than 1/10 of that in the ternary Al–Mg–Si system. The excess Si in the alloy remains as coarse Mg2Si dispersoids which produce no significant age-Hardening effect. Interestingly, a small change of Si content (from 0.061 at.% to 0.093 at.%) in the solid solution of the alloy has been found to be effective in modifying precipitation microstructure by promoting the formation of fine Guinier–Preston–Bagaryasky (GPB) zones and postponing the formation of the S phase during ageing at 200 °C. Consequently, the quaternary alloy exhibits an enhanced age-Hardening Response during earlier-stage ageing.
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Si-induced precipitation modification and related age-Hardening Response of an Al–4Mg–1Cu–0.5Si alloy
Materials Chemistry and Physics, 2017Co-Authors: Gang Sha, J. H. Xia, Yongchang Liu, Simon P. RingerAbstract:Abstract The solid solubility of Si in a quaternary Al–4Mg–1Cu–0.5Si (wt%) alloy has been found to be only about 0.061 at% at 520 °C, and 0.093 at% at 560 °C, less than 1/10 of that in the ternary Al–Mg–Si system. The excess Si in the alloy remains as coarse Mg2Si dispersoids which produce no significant age-Hardening effect. Interestingly, a small change of Si content (from 0.061 at.% to 0.093 at.%) in the solid solution of the alloy has been found to be effective in modifying precipitation microstructure by promoting the formation of fine Guinier–Preston–Bagaryasky (GPB) zones and postponing the formation of the S phase during ageing at 200 °C. Consequently, the quaternary alloy exhibits an enhanced age-Hardening Response during earlier-stage ageing.
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Enhanced bake-Hardening Response of an Al–Mg–Si–Cu alloy with Zn addition
Materials Chemistry and Physics, 2015Co-Authors: Mingxing Guo, Gang Sha, Lingyong Cao, W.q. Liu, Jin Zhang, Linzhong ZhuangAbstract:Abstract This study reports that Zn addition greatly enhances the bake-Hardening Response of an Al–Mg–Si–Cu alloy. The pre-aged alloy exhibits a high strength increment of 135 MPa after paint baking. Differential scanning calorimetry, atom probe tomography and high-resolution transmission electron microscopy reveal that Zn addition and pre-aging have significant effects on the solute nanostructure formation. Zn atoms partition into solute clusters/GP zones, and reduce the activation energy of β” precipitation in the alloy.
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effect of solution treatment on precipitation and age Hardening Response of an al 4mg 1cu 0 5si 0 4ag wt alloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2014Co-Authors: Gang Sha, J. H. Xia, B. Gun, J. Z. Cui, Xiaotao Liu, Simon P. RingerAbstract:Abstract An increase in solution temperature from 520 °C to 560 °C doubled Si concentration (from 0.06 at% to 0.13 at%) in the solid solution of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy. Consequently, the alloy exhibited an enhanced age-Hardening Response with a peak hardness of 135 HVN, 10% higher than that of the alloy treated at 520 °C. The treatment at 560 °C enabled the formation of more Guinier–Preston–Bagaryasky (GPB) zones rather than the Z-phase during subsequent ageing at 200 °C, and hence produced an enhanced strengthening effect to the alloy.
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Effect of solution treatment on precipitation and age-Hardening Response of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy
Materials Science and Engineering: A, 2014Co-Authors: Gang Sha, J. H. Xia, B. Gun, J. Z. Cui, Xiaotao Liu, Simon P. RingerAbstract:Abstract An increase in solution temperature from 520 °C to 560 °C doubled Si concentration (from 0.06 at% to 0.13 at%) in the solid solution of an Al–4Mg–1Cu–0.5Si–0.4Ag (wt%) alloy. Consequently, the alloy exhibited an enhanced age-Hardening Response with a peak hardness of 135 HVN, 10% higher than that of the alloy treated at 520 °C. The treatment at 560 °C enabled the formation of more Guinier–Preston–Bagaryasky (GPB) zones rather than the Z-phase during subsequent ageing at 200 °C, and hence produced an enhanced strengthening effect to the alloy.
Qingshan Dong - One of the best experts on this subject based on the ideXlab platform.
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effect of solidification cooling rate on kinetics of continuous discontinuous al3 sc zr precipitation and the subsequent age Hardening Response in cold rolled almgsc zr sheets
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2020Co-Authors: Qingshan Dong, Andrew Howells, David James Lloyd, Mark Gallerneault, Vahid FallahAbstract:Abstract We explain the critical effect of casting processing route (i.e., the solidification cooling rate) on the kinetics of Sc–Zr precipitation upon solidification and, subsequently, on the age-Hardening Response of cold-rolled/aged Al–3Mg-0.36Sc-0.14Zr sheets. The evolution mechanisms of various types of Al3(Sc,Zr) precipitates are investigated in the as-cast specimens (fabricated via strip casting vs. mold casting techniques), as well as in the subsequently cold-rolled/aged sheet specimens. The Al3(Sc,Zr) precipitates appeared to have formed upon either discontinuous or continuous precipitation during cooling from solidification temperatures; the former leads to the formation of lamellar Al3(Sc,Zr) cells while the latter results in the formation of spherical precipitates, all of which possessing an L12 crystal structure and a coherent interface with the α-Al matrix. It is shown that slower cooling rates via mold casting lead to the occurrence of both continuous and discontinuous precipitation upon cooling from the solidification temperature. In contrast, higher cooling rates via strip casting results in the apparent prevention of all discontinuous precipitation reactions as well as in the suppression of continuous precipitation. The overall effect is the greater preservation of Sc supersaturation within the α-Al matrix of the as-cast specimens fabricated via strip casting which, subsequently, leads to higher precipitation kinetics and thus higher tensile properties upon age-Hardening of the cold-rolled sheets.
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Effect of solidification cooling rate on kinetics of continuous/discontinuous Al3(Sc,Zr) precipitation and the subsequent age-Hardening Response in cold-rolled AlMgSc(Zr) sheets
Materials Science and Engineering: A, 2020Co-Authors: Qingshan Dong, Andrew Howells, David James Lloyd, Mark Gallerneault, Vahid FallahAbstract:Abstract We explain the critical effect of casting processing route (i.e., the solidification cooling rate) on the kinetics of Sc–Zr precipitation upon solidification and, subsequently, on the age-Hardening Response of cold-rolled/aged Al–3Mg-0.36Sc-0.14Zr sheets. The evolution mechanisms of various types of Al3(Sc,Zr) precipitates are investigated in the as-cast specimens (fabricated via strip casting vs. mold casting techniques), as well as in the subsequently cold-rolled/aged sheet specimens. The Al3(Sc,Zr) precipitates appeared to have formed upon either discontinuous or continuous precipitation during cooling from solidification temperatures; the former leads to the formation of lamellar Al3(Sc,Zr) cells while the latter results in the formation of spherical precipitates, all of which possessing an L12 crystal structure and a coherent interface with the α-Al matrix. It is shown that slower cooling rates via mold casting lead to the occurrence of both continuous and discontinuous precipitation upon cooling from the solidification temperature. In contrast, higher cooling rates via strip casting results in the apparent prevention of all discontinuous precipitation reactions as well as in the suppression of continuous precipitation. The overall effect is the greater preservation of Sc supersaturation within the α-Al matrix of the as-cast specimens fabricated via strip casting which, subsequently, leads to higher precipitation kinetics and thus higher tensile properties upon age-Hardening of the cold-rolled sheets.
