TY - JOUR

T1 - Synergistic alloy design concept for new high-strength Al–Mg–Si thick plate alloys

AU - Schmid, Florian

AU - Weißensteiner, Irmgard

AU - Tunes, Matheus A.

AU - Kremmer, Thomas

AU - Ebner, Thomas

AU - Morak, Roland

AU - Uggowitzer, Peter J.

AU - Pogatscher, Stefan

N1 - Publisher Copyright: © 2021 Acta Materialia Inc.

PY - 2021/3

Y1 - 2021/3

N2 - With the aim of fully exploiting the advantageous strength-to-weight ratio evident in Al–Mg–Si alloys, this study presents measures for increasing the yield strength of an EN AW-6082 type plate alloy. In addition to describing the thermodynamic simulation-based adjustment of age-hardenable elements (Si, Mg and Cu) and a modified artificial ageing treatment, it investigates the effects of adding a small amount of Zr. The significant strengthening induced by adding Zr is correlated with sub-grain boundary hardening in a recovered microstructure after solution annealing at 570 °C, compared with the almost entirely recrystallized microstructure in an unmodified EN AW-6082 alloy. In combination with a maximum dissolvable number of age-hardenable elements and interrupted quenching, which comprises an improved heat treatment strategy for thick plates, it is seen that the yield strength can be increased by more than 40% to 411 MPa compared to conventional EN AW-6082 base material as verified by tensile testing. In the study scanning electron microscopy and scanning transmission electron microscopy were performed for microstructural characterization with a focus on particle and deformation analysis. All individual contributions which generated the superior strength are calculated and discussed in order to reveal the microstructure-property relationship.

AB - With the aim of fully exploiting the advantageous strength-to-weight ratio evident in Al–Mg–Si alloys, this study presents measures for increasing the yield strength of an EN AW-6082 type plate alloy. In addition to describing the thermodynamic simulation-based adjustment of age-hardenable elements (Si, Mg and Cu) and a modified artificial ageing treatment, it investigates the effects of adding a small amount of Zr. The significant strengthening induced by adding Zr is correlated with sub-grain boundary hardening in a recovered microstructure after solution annealing at 570 °C, compared with the almost entirely recrystallized microstructure in an unmodified EN AW-6082 alloy. In combination with a maximum dissolvable number of age-hardenable elements and interrupted quenching, which comprises an improved heat treatment strategy for thick plates, it is seen that the yield strength can be increased by more than 40% to 411 MPa compared to conventional EN AW-6082 base material as verified by tensile testing. In the study scanning electron microscopy and scanning transmission electron microscopy were performed for microstructural characterization with a focus on particle and deformation analysis. All individual contributions which generated the superior strength are calculated and discussed in order to reveal the microstructure-property relationship.

KW - Alloy design

KW - Aluminum alloys

KW - Precipitation strengthening

KW - Wrought alloys

UR - https://doi.org/10.1016/j.mtla.2020.100997

UR - http://www.scopus.com/inward/record.url?scp=85099253029&partnerID=8YFLogxK

U2 - 10.1016/j.mtla.2020.100997

DO - 10.1016/j.mtla.2020.100997

M3 - Article

VL - 15

JO - Materialia

JF - Materialia

SN - 2589-1529

M1 - 100997

ER -