1. Effects of Al–Ti–C–Ce Master Alloy on Microstructure and Mechanical Properties of Hypoeutectic Al–7%Si Alloy
- Author
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Qiao Jisen, Wanwu Ding, Xiaoyan Zhao, Xinchang Tang, Tiandong Xia, Tingbiao Guo, and Wenjun Zhao
- Subjects
Equiaxed crystals ,Materials science ,020502 materials ,Alloy ,Metals and Alloys ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,Microstructure ,Industrial and Manufacturing Engineering ,020501 mining & metallurgy ,0205 materials engineering ,chemistry ,Mechanics of Materials ,Aluminium ,Phase (matter) ,Ultimate tensile strength ,Materials Chemistry ,engineering ,Composite material ,Elongation ,Eutectic system - Abstract
It is well known that the mechanical properties of hypoeutectic Al–7%Si alloys are influenced by the size, morphology, and distribution of primary α-Al and eutectic Si crystals. In the present work, a novel Al–Ti–C–Ce master alloy was prepared by the pure molten aluminum thermal explosion reaction, and its effects on the microstructure and mechanical properties of hypoeutectic Al–7%Si alloy were investigated. The results show that the Al–Ti–C–Ce master alloy containing α-Al, granular TiC, lump-like TiAl3, and block-like Ti2Al20Ce has excellent refining and modification properties for hypoeutectic Al–7%Si alloy. When 1.5 wt.% Al–Ti–C–Ce master alloy is added, the coarse dendritic α-Al in hypoeutectic Al–7%Si alloy is refined into equiaxed grains. The secondary dendritic arm spacing (SDAS) was also reduced, and the coarse needle-flake eutectic Si phase was transformed into a fibrous and granular phase. It was found that the ultimate tensile strength and elongation increased by 59% and 56%, respectively, due to the decrease in the SDAS of primary α-Al dendrites and the modification of eutectic Si crystals. Moreover, the change of mechanical properties corresponds to the evolution of microstructure.
- Published
- 2018