Abstract
The effects of the grain structure direction on the impact properties and dislocation substructure of 6061-T6 aluminium alloy are investigated under room temperature conditions and strain rates of 16103, 36103 and 56103 s21 using a split-Hopkinson pressure bar system. The impact tests are performed using specimens machined from rolled 6061-T6 plates in the longitudinal, transverse and through thickness directions respectively. The results show that for all specimens, the flow stress increases with increasing strain rate. Furthermore, for all strain rates, the highest flow stress occurs in the transverse specimen. For strain rates of 16103 and 36103 s21, the flow stress in the through thickness specimen is greater than that in the longitudinal specimen. However, at a strain rate of 56103 s21, the flow stress in the longitudinal specimen is higher than that in the through thickness specimen due to a greater dislocation multiplication rate. For all three grain structure directions, the strain rate sensitivity increases with increasing strain rate, but decreases with increasing true strain. The highest strain rate sensitivity is observed in the longitudinal specimen at strain rates of 36103 to 56103 s21. The dislocation density increases markedly with increasing strain rate. Moreover, the square root of the dislocation density varies as a linear function of the flow stress in accordance with the Bailey-Hirsch relationship. The strengthening effect produced by the increased dislocation density is particularly evident in the transverse specimen, followed by the longitudinal specimen and the through thickness specimen.
| Original language | English |
|---|---|
| Pages (from-to) | 1719-1727 |
| Number of pages | 9 |
| Journal | Materials Science and Technology (United Kingdom) |
| Volume | 30 |
| Issue number | 14 |
| DOIs | |
| Publication status | Published - 2014 Nov 1 |
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
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Effects of directional grain structure on impact properties and dislocation substructure of 6061-T6 aluminium alloy. / Lee, Woei-Shyan; Liu, M. H.
In: Materials Science and Technology (United Kingdom), Vol. 30, No. 14, 01.11.2014, p. 1719-1727.Research output: Contribution to journal › Article
TY - JOUR
T1 - Effects of directional grain structure on impact properties and dislocation substructure of 6061-T6 aluminium alloy
AU - Lee, Woei-Shyan
AU - Liu, M. H.
PY - 2014/11/1
Y1 - 2014/11/1
N2 - The effects of the grain structure direction on the impact properties and dislocation substructure of 6061-T6 aluminium alloy are investigated under room temperature conditions and strain rates of 16103, 36103 and 56103 s21 using a split-Hopkinson pressure bar system. The impact tests are performed using specimens machined from rolled 6061-T6 plates in the longitudinal, transverse and through thickness directions respectively. The results show that for all specimens, the flow stress increases with increasing strain rate. Furthermore, for all strain rates, the highest flow stress occurs in the transverse specimen. For strain rates of 16103 and 36103 s21, the flow stress in the through thickness specimen is greater than that in the longitudinal specimen. However, at a strain rate of 56103 s21, the flow stress in the longitudinal specimen is higher than that in the through thickness specimen due to a greater dislocation multiplication rate. For all three grain structure directions, the strain rate sensitivity increases with increasing strain rate, but decreases with increasing true strain. The highest strain rate sensitivity is observed in the longitudinal specimen at strain rates of 36103 to 56103 s21. The dislocation density increases markedly with increasing strain rate. Moreover, the square root of the dislocation density varies as a linear function of the flow stress in accordance with the Bailey-Hirsch relationship. The strengthening effect produced by the increased dislocation density is particularly evident in the transverse specimen, followed by the longitudinal specimen and the through thickness specimen.
AB - The effects of the grain structure direction on the impact properties and dislocation substructure of 6061-T6 aluminium alloy are investigated under room temperature conditions and strain rates of 16103, 36103 and 56103 s21 using a split-Hopkinson pressure bar system. The impact tests are performed using specimens machined from rolled 6061-T6 plates in the longitudinal, transverse and through thickness directions respectively. The results show that for all specimens, the flow stress increases with increasing strain rate. Furthermore, for all strain rates, the highest flow stress occurs in the transverse specimen. For strain rates of 16103 and 36103 s21, the flow stress in the through thickness specimen is greater than that in the longitudinal specimen. However, at a strain rate of 56103 s21, the flow stress in the longitudinal specimen is higher than that in the through thickness specimen due to a greater dislocation multiplication rate. For all three grain structure directions, the strain rate sensitivity increases with increasing strain rate, but decreases with increasing true strain. The highest strain rate sensitivity is observed in the longitudinal specimen at strain rates of 36103 to 56103 s21. The dislocation density increases markedly with increasing strain rate. Moreover, the square root of the dislocation density varies as a linear function of the flow stress in accordance with the Bailey-Hirsch relationship. The strengthening effect produced by the increased dislocation density is particularly evident in the transverse specimen, followed by the longitudinal specimen and the through thickness specimen.
UR - http://www.scopus.com/inward/record.url?scp=84987813251&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84987813251&partnerID=8YFLogxK
U2 - 10.1179/1743284713Y.0000000456
DO - 10.1179/1743284713Y.0000000456
M3 - Article
VL - 30
SP - 1719
EP - 1727
JO - Materials Science and Technology
JF - Materials Science and Technology
SN - 0267-0836
IS - 14
ER -