Refinement of primary Si grains in AI-20% Si alloy slurry through serpentine channel pouring process

• Published in: 矿物冶金与材料学报：英文版 2016, Vol.23 (5), p.572-580
• Main Author: Zhi-kai Zheng Wei-min Mao Zhi-yong Liu Dong Wang Rui Yue
• Format: Article
• Language: English
• Subjects: Al-Si合金; 初生硅; 半固态浆料; 浇注温度; 蛇; 通道; 金浆料; 颗粒尺寸
• ISSN: 1674-4799; 1869-103X

In this study, a serpentine channel pouring process was used to prepare the semi-solid A1-20%Si alloy slurry and refine primary Si grains in the alloy. The effects of the pouring temperature, number of curves in the serpentine channel, and material of the serpentine channel on the size of primary Si grains in the semi-solid A1-20%Si alloy slurry were investigated. The results showed that the pouting temperature, number of the curves, and material of the channel strongly affected the size and distribution of the primary Si grains. The pouring tempera- ture exerted the strongest effect, followed by the number of the curves and then the material of the channel. Under experimental conditions of a four-curve copper channel and a pouring temperature of 701℃, primary Si grains in the semi-solid A1-20%Si alloy slurry were refined to the greatest extent, and the lath-like grains were changed into granular grains. Moreover, the equivalent grain diameter and the average shape coefficient of primary Si grains in the satisfactory semi-solid A1-20%Si alloy slurry were 24.4 μm and 0.89, respectively. Finally, the re- finement mechanism and distribution rule of primary Si grains in the slurry prepared through the serpentine channel pouring process were analyzed and discussed.