Study on Microstructure and Mechanical Properties of Hypereutectic Al-18Si Alloy Modified with Al-3B

Chunjie Gong; Hao Tu; Changjun Wu; Jianhua Wang; Xuping Su

doi:10.3390/ma11030456

Study on Microstructure and Mechanical Properties of Hypereutectic Al-18Si Alloy Modified with Al-3B

Materials (Basel). 2018 Mar 20;11(3):456. doi: 10.3390/ma11030456.

Authors

Chunjie Gong^{1

2

3}, Hao Tu^{4

5

6}, Changjun Wu^{7

8

9}, Jianhua Wang^{10

11

12}, Xuping Su^{13

14

15}

Affiliations

¹ Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China. gongchunjie2000@foxmail.com.
² Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China. gongchunjie2000@foxmail.com.
³ National Experimental Teaching Demonstration Center of Material Science and Engineering, Changzhou University, Changzhou 213164, China. gongchunjie2000@foxmail.com.
⁴ Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China. tuhao@cczu.edu.cn.
⁵ Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China. tuhao@cczu.edu.cn.
⁶ National Experimental Teaching Demonstration Center of Material Science and Engineering, Changzhou University, Changzhou 213164, China. tuhao@cczu.edu.cn.
⁷ Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China. wucj@cczu.edu.cn.
⁸ Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China. wucj@cczu.edu.cn.
⁹ National Experimental Teaching Demonstration Center of Material Science and Engineering, Changzhou University, Changzhou 213164, China. wucj@cczu.edu.cn.
¹⁰ Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China. wangjh@cczu.edu.cn.
¹¹ Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China. wangjh@cczu.edu.cn.
¹² National Experimental Teaching Demonstration Center of Material Science and Engineering, Changzhou University, Changzhou 213164, China. wangjh@cczu.edu.cn.
¹³ Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Changzhou 213164, China. sxping@cczu.edu.cn.
¹⁴ Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Changzhou University, Changzhou 213164, China. sxping@cczu.edu.cn.
¹⁵ National Experimental Teaching Demonstration Center of Material Science and Engineering, Changzhou University, Changzhou 213164, China. sxping@cczu.edu.cn.

Abstract

An hypereutectic Al-18Si alloy was modified via an Al-3B master alloy. The effect of the added Al-3B and the modification temperature on the microstructure, tensile fracture morphologies, and mechanical properties of the alloy were investigated using an optical microscope, Image-Pro Plus 6.0, a scanning electron microscope, and a universal testing machine. The results show that the size of the primary Si and its fraction decreased at first, and then increased as an additional amount of Al-3B was added. When the added Al-3B reached 0.2 wt %, the fraction of the primary Si in the Al-18Si alloy decreased with an increase in temperature. Compared with the unmodified Al-18Si alloy, the tensile strength and elongation of the alloy modified at 850 °C with 0.2 wt % Al-3B increased by 25% and 81%, respectively. The tensile fracture of the modified Al-18Si alloy exhibited partial ductile fracture characteristics, but there were more areas with ductile characteristics compared with that of the unmodified Al-18Si alloy.

Keywords: hypereutectic Al–18Si alloy; mechanical properties; microstructure; modification.