Grain refinement of AZ91D magnesium alloy by Al-Ti-B master alloy and its effect on mechanical properties

doi:10.1016/j.matdes.2011.05.020

	Grain refinement of AZ91D magnesium alloy by Al-Ti-B master alloy and its effect on mechanical properties
	Chen, T. J.; Wang, R. Q.; Ma, Y.; Hao, Y.
刊名	MATERIALS & DESIGN
	2012-02
卷号	34 页码:637-648
关键词	Non-ferrous metals and alloys Mechanical Microstructure
ISSN号	0261-3069
DOI	10.1016/j.matdes.2011.05.020
英文摘要	The effects of grain-refining parameters on grain size of AZ91D alloy have been investigated using an Al-Ti-B master alloy as refiner and an adequate refining technique has been developed. Simultaneously, the ultimate tensile strength (UTS) and hardness of the as-cast, solutionized and solution-aged alloys have also been examined at room temperature. The results indicate that the Al-Ti-B master alloy is an effective grain refiner for AZ91D alloy. Increasing pouring temperature or cooling rate from holding temperature to pouring temperature is beneficial for obtaining small grains. But for addition amount, holding temperature or holding time, there is an optimal value. The grain size can be decreased from 422 mu m to 79 mu m after being refined according to the obtained technique. Accordingly, both the UTS and hardness are obviously enhanced. Solution treatment can further improve the UTS but decrease the hardness while solution-age treatment leads these two properties to increase. Compared with the un-refined as-cast alloy, the UTS and hardness of the solution-aged alloy are increased by 71% and 53% respectively. Correspondingly, the fracture mode during tensile testing changes with the treatments. These changes in mechanical properties and fracture mode are attributed to the different contributions of dissolution or precipitation of beta phase to grain bonding strength, solution strengthening and precipitation strengthening. In addition, the microstructure sensitivity of the alloy refined by this refiner to casting thickness is quite low compared with that of the alloy refined by SiC particles. (C) 2011 Elsevier Ltd. All rights reserved.
资助项目	National Basic Research Program of China[G2007CB613706]
WOS研究方向	Materials Science
语种	英语
出版者	ELSEVIER SCI LTD
WOS记录号	WOS:000298120300085
状态	已发表
内容类型	期刊论文
源URL	[http://119.78.100.223/handle/2XXMBERH/34945]
专题	材料科学与工程学院
通讯作者	Chen, T. J.
作者单位	Lanzhou Univ Technol, Key Lab Gansu Adv Nonferrous Met Mat, Lanzhou 730050, Peoples R China
推荐引用方式 GB/T 7714	Chen, T. J.,Wang, R. Q.,Ma, Y.,et al. Grain refinement of AZ91D magnesium alloy by Al-Ti-B master alloy and its effect on mechanical properties[J]. MATERIALS & DESIGN,2012,34:637-648.
APA	Chen, T. J.,Wang, R. Q.,Ma, Y.,&Hao, Y..(2012).Grain refinement of AZ91D magnesium alloy by Al-Ti-B master alloy and its effect on mechanical properties.MATERIALS & DESIGN,34,637-648.
MLA	Chen, T. J.,et al."Grain refinement of AZ91D magnesium alloy by Al-Ti-B master alloy and its effect on mechanical properties".MATERIALS & DESIGN 34(2012):637-648.