TY - JOUR
T1 - Tensile deformation behavior of triple heterogeneous microstructure comprising fine equiaxed/coarse equiaxed/columnar grains in AlCu/AlMgSc bimetal fabricated via dual-wire arc direct energy deposition
AU - Zhou, Yinghui
AU - Fang, Xuewei
AU - Lin, Xin
AU - Jian, Zengyun
AU - Huang, Shixing
AU - Wu, Yue
AU - Meng, Jie
AU - Yang, Wenzhe
N1 - Publisher Copyright:
© 2024
PY - 2024/9/10
Y1 - 2024/9/10
N2 - In this study, an AlCu/AlMgSc bimetallic alloy is prepared using a dual-wire arc direct energy deposition method and a triple heterogeneous microstructure (fine/coarse equiaxed grains/columnar grains) is constructed. Additionally, a quantitative comparative analysis of the deformation behavior of triple and dual heterogeneous microstructures during interrupted tensile testing is conducted, with emphasis on the effects of grain morphology and size on the tensile deformation mechanisms in the heterogeneous microstructure. Compared with the AlCu alloy with a double heterogeneous microstructure (equiaxed/columnar grain), the AlCu/AlMgSc bimetallic alloy exhibits a higher ultimate tensile strength of 301.4 ± 7.9 MPa, a yield strength of 181.3 ± 1.4 MPa, and an elongation of 9.7 % ± 1.3 %, which correspond to increases by 19.4 %, 21.2 %, and 24.4 %, respectively. Interrupted tensile testing is performed and a quasi-in-situ approach is employed to investigate the plastic deformation mechanisms of the triple heterogeneous microstructure during tensile deformation. The density of geometrically necessary dislocations (GNDs) in the fine equiaxed grains and the rate of GND accumulation during deformation, surpassed those observed in coarse equiaxed and columnar grains. Furthermore, in micrometer-sized equiaxed grains, the ability to accumulate GNDs decreases as the equiaxed grain size increases, and the equiaxed grains exhibit a higher capacity to accumulate GNDs compared with columnar grains. The triple heterogeneous microstructure provides a more favorable environment for trapping GNDs, thus resulting in enhanced strength and plastic deformation capabilities. This study offers guidance for the formulation and engineering application of heterogeneous microstructure alloys with diverse grain morphologies and multiple length scales. Additionally, novel approaches are introduced to enhance the strength and ductility of Al alloys.
AB - In this study, an AlCu/AlMgSc bimetallic alloy is prepared using a dual-wire arc direct energy deposition method and a triple heterogeneous microstructure (fine/coarse equiaxed grains/columnar grains) is constructed. Additionally, a quantitative comparative analysis of the deformation behavior of triple and dual heterogeneous microstructures during interrupted tensile testing is conducted, with emphasis on the effects of grain morphology and size on the tensile deformation mechanisms in the heterogeneous microstructure. Compared with the AlCu alloy with a double heterogeneous microstructure (equiaxed/columnar grain), the AlCu/AlMgSc bimetallic alloy exhibits a higher ultimate tensile strength of 301.4 ± 7.9 MPa, a yield strength of 181.3 ± 1.4 MPa, and an elongation of 9.7 % ± 1.3 %, which correspond to increases by 19.4 %, 21.2 %, and 24.4 %, respectively. Interrupted tensile testing is performed and a quasi-in-situ approach is employed to investigate the plastic deformation mechanisms of the triple heterogeneous microstructure during tensile deformation. The density of geometrically necessary dislocations (GNDs) in the fine equiaxed grains and the rate of GND accumulation during deformation, surpassed those observed in coarse equiaxed and columnar grains. Furthermore, in micrometer-sized equiaxed grains, the ability to accumulate GNDs decreases as the equiaxed grain size increases, and the equiaxed grains exhibit a higher capacity to accumulate GNDs compared with columnar grains. The triple heterogeneous microstructure provides a more favorable environment for trapping GNDs, thus resulting in enhanced strength and plastic deformation capabilities. This study offers guidance for the formulation and engineering application of heterogeneous microstructure alloys with diverse grain morphologies and multiple length scales. Additionally, novel approaches are introduced to enhance the strength and ductility of Al alloys.
KW - AlCu/AlMgSc bimetallic alloy
KW - Dual-wire arc direct energy deposition
KW - Geometrically necessary dislocations
KW - Mechanical properties
KW - Triple heterogeneous microstructure
UR - http://www.scopus.com/inward/record.url?scp=85188691396&partnerID=8YFLogxK
U2 - 10.1016/j.jmst.2023.11.026
DO - 10.1016/j.jmst.2023.11.026
M3 - 文章
AN - SCOPUS:85188691396
SN - 1005-0302
VL - 193
SP - 160
EP - 177
JO - Journal of Materials Science and Technology
JF - Journal of Materials Science and Technology
ER -