TY - JOUR
T1 - Shock wave determination of the strengthening of commercial aluminum alloy 6061 by point defects
AU - Zaretsky, E. B.
AU - Frage, N.
AU - Kalabukhov, S.
N1 - Funding Information:
Financial support from the Israel Science Foundation (grant 441/18 ) to N. Frage and E.B. Zaretsky and from the Israeli Ministry of Defense (grant 87576431 ) to E.B. Zaretsky are gratefully acknowledged.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/7/22
Y1 - 2019/7/22
N2 - The strengthening of aluminum alloy 6061 (AA6061) by different point defects was determined experimentally using a shock wave technique. Decay of the amplitude of elastic precursor wave τel with propagation distance h was studied in four groups of AA6061 samples, namely, that in the super-saturated solid solution state (SSSS), and those strengthened by atomic clusters (short-range order), by Guinier-Preston zones I and by Guinier-Preston zones II after, respectively 7.5, 240 and 960 min aging of the SSSS samples at 145 °C. The dependences τel(h) were found to be kinked at stress τ*, corresponding to the transition of the control of dislocation motion from phonon viscous drag at τel>τ* to thermally activated obstacle passage at τel<τ*. The values of strengthening by atomic clusters, GP-I, and GP-II zones were found equal to τsro=67, τGP-I=67, and τGP-II=124MPa, respectively. Activation volumes corresponding to the interaction of dislocations with the studied defects, estimated based on τel<τ* segments of the measured dependences τel(h), were found to be in reasonable agreement with existing concepts of dislocation/defect interactions.
AB - The strengthening of aluminum alloy 6061 (AA6061) by different point defects was determined experimentally using a shock wave technique. Decay of the amplitude of elastic precursor wave τel with propagation distance h was studied in four groups of AA6061 samples, namely, that in the super-saturated solid solution state (SSSS), and those strengthened by atomic clusters (short-range order), by Guinier-Preston zones I and by Guinier-Preston zones II after, respectively 7.5, 240 and 960 min aging of the SSSS samples at 145 °C. The dependences τel(h) were found to be kinked at stress τ*, corresponding to the transition of the control of dislocation motion from phonon viscous drag at τel>τ* to thermally activated obstacle passage at τel<τ*. The values of strengthening by atomic clusters, GP-I, and GP-II zones were found equal to τsro=67, τGP-I=67, and τGP-II=124MPa, respectively. Activation volumes corresponding to the interaction of dislocations with the studied defects, estimated based on τel<τ* segments of the measured dependences τel(h), were found to be in reasonable agreement with existing concepts of dislocation/defect interactions.
KW - Control of dislocation motion
KW - Elastic precursor decay
KW - Point defects in aluminum alloy 6061
UR - http://www.scopus.com/inward/record.url?scp=85067889321&partnerID=8YFLogxK
U2 - 10.1016/j.msea.2019.138066
DO - 10.1016/j.msea.2019.138066
M3 - Article
AN - SCOPUS:85067889321
SN - 0921-5093
VL - 761
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
M1 - 138066
ER -