Effect of Micro-Alloying Element La on Solidification Microstructure and Mechanical Properties of Hypoeutectic Al-Si Alloys

doi:10.11900/0412.1961.2020.00158

IMR OpenIR

	Effect of Micro-Alloying Element La on Solidification Microstructure and Mechanical Properties of Hypoeutectic Al-Si Alloys
	Zheng Qiuju 1,2; Ye Zhongfei 3; Jiang Hongxiang 1; Lu Ming 3; Zhang Lili 1; Zhao Jiuzhou 1,2
通讯作者	Zhao Jiuzhou(jzzhao@imr.ac.cn)
	2021-01-11
发表期刊	ACTA METALLURGICA SINICA
ISSN	0412-1961
卷号	57 期号:1 页码:103-110
摘要	Hypoeutectic Al-Si alloys are extensively used in the welding industry owing to their excellent cast-ability, low coefficient of thermal expansion, and good weldability. Unfortunately, Al-Si alloys solidify under conventional cooling conditions, forming coarse dendritic alpha-Al grains with an eutectic structure and a flake-like morphology that has poor mechanical properties. Chemical inoculations are often used to control the size of alpha-Al grains and the morphology of the eutectic Si particles. The grain refiner Al-Ti-B master alloy and eutectic Si modifier Sr are commonly used in industry. In recent years, great attention has been paid to controlling the microstructure and mechanical properties of hypoeutectic Al-Si alloys through the use of the cost-effective rare earth element La. Previous studies have mainly focused on the effects of La addition on the microstructural evolution and improvements of the mechanical properties. However, to date there have been no studies on the effects of combined addition of La, Al-Ti-B master alloy and Sr on the microstructure and mechanical properties of Al-Si alloys. In this work, solidification experiments were performed to investigate the effects of the micro-alloying element La, Al-Ti-B master alloy, and Sr on the solidification microstructure and mechanical properties of hypoeutectic Al-Si alloys. These results show that synergistic effects are achieved by combinations of La, Al-Ti-B master alloy, and Sr. An addition of 0.06%La was sufficient for effective alpha-Al grain refinement, eutectic Si particle modification, and improved the ductility of the alloys. Excess La addition formed a coarse LaAlSi intermetallic compound, which deteriorated the ductility of the alloy. The micro-alloying element La refined the alpha-Al grains by acting as a surfactant that decreased the wetting angle between the TiB2 nucleation substrate and the alpha-Al nucleus. It modified the eutectic Si particles by promoting the formation of the multiple Si twins and changing the growth behaviors of the Si particles.
关键词	Al-Si alloy micro-alloying element La solidification microstructure mechanical property
资助者	National Natural Science Foundation of China ; Science and Technology Project of the Headquarters of Sate Grid Company of China
DOI	10.11900/0412.1961.2020.00158
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[51771210] ; National Natural Science Foundation of China[51971227] ; Science and Technology Project of the Headquarters of Sate Grid Company of China
WOS研究方向	Metallurgy & Metallurgical Engineering
WOS类目	Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000624917400009
出版者	SCIENCE PRESS
引用统计	被引频次：6[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/161281
专题	中国科学院金属研究所
通讯作者	Zhao Jiuzhou
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, Shenyang 110016, Peoples R China 3.State Grid Henan Elect Power Co, Elect Power Res Inst, Zhengzhou 450052, Peoples R China
推荐引用方式 GB/T 7714	Zheng Qiuju,Ye Zhongfei,Jiang Hongxiang,et al. Effect of Micro-Alloying Element La on Solidification Microstructure and Mechanical Properties of Hypoeutectic Al-Si Alloys[J]. ACTA METALLURGICA SINICA,2021,57(1):103-110.
APA	Zheng Qiuju,Ye Zhongfei,Jiang Hongxiang,Lu Ming,Zhang Lili,&Zhao Jiuzhou.(2021).Effect of Micro-Alloying Element La on Solidification Microstructure and Mechanical Properties of Hypoeutectic Al-Si Alloys.ACTA METALLURGICA SINICA,57(1),103-110.
MLA	Zheng Qiuju,et al."Effect of Micro-Alloying Element La on Solidification Microstructure and Mechanical Properties of Hypoeutectic Al-Si Alloys".ACTA METALLURGICA SINICA 57.1(2021):103-110.