TY - JOUR
T1 - Non-axially oriented dendritic microstructures and their mechanical characteristics of single-crystal Al-4.5%Cu alloy
AU - Wang, Yumin
AU - Li, Shuangming
AU - Yang, Bin
AU - Liu, Zhenpeng
AU - Zhong, Hong
AU - Xing, Hui
AU - Wang, Huamiao
N1 - Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2020/1/13
Y1 - 2020/1/13
N2 - This study investigated microstructure formation as a function of orientation-dependent surface tension anisotropy during directional solidification of Al-4.5%Cu alloy. Axial dendrites (AD), tilted dendrite (TD), and degenerate pattern (DP) were identified in the solidified microstructures of the single crystals. A single-crystal specimen with a stable DP, which was characterized by successive splitting tips, was carefully prepared and specifically investigated. The corresponding mechanical properties were compared with those of single-crystal AD and TD specimens. The ductility and toughness of the single-crystal specimen with a DP were approximately 91% and 87% higher than those of the other specimens, respectively. Moreover, the DP specimen showed a stronger work hardening effect than the other specimens, and the tip splitting in this specimen gave rise to refined θ′ precipitates. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) characterizations uncovered the underlying mechanisms associated with this enhancement. This study provides insightful knowledge regarding microstructure control and enriches the understanding of mechanical properties for different dendritic patterns.
AB - This study investigated microstructure formation as a function of orientation-dependent surface tension anisotropy during directional solidification of Al-4.5%Cu alloy. Axial dendrites (AD), tilted dendrite (TD), and degenerate pattern (DP) were identified in the solidified microstructures of the single crystals. A single-crystal specimen with a stable DP, which was characterized by successive splitting tips, was carefully prepared and specifically investigated. The corresponding mechanical properties were compared with those of single-crystal AD and TD specimens. The ductility and toughness of the single-crystal specimen with a DP were approximately 91% and 87% higher than those of the other specimens, respectively. Moreover, the DP specimen showed a stronger work hardening effect than the other specimens, and the tip splitting in this specimen gave rise to refined θ′ precipitates. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) characterizations uncovered the underlying mechanisms associated with this enhancement. This study provides insightful knowledge regarding microstructure control and enriches the understanding of mechanical properties for different dendritic patterns.
KW - Degenerate pattern
KW - Directional solidification
KW - Mechanical properties
KW - Surface tension anisotropy
UR - https://www.scopus.com/pages/publications/85075349378
U2 - 10.1016/j.msea.2019.138665
DO - 10.1016/j.msea.2019.138665
M3 - 文章
AN - SCOPUS:85075349378
SN - 0921-5093
VL - 771
JO - Materials Science and Engineering: A
JF - Materials Science and Engineering: A
M1 - 138665
ER -