Achieving superior low temperature and high strain rate superplasticity in submerged friction stir welded Ti-6Al-4V alloy

IMR OpenIR

	Achieving superior low temperature and high strain rate superplasticity in submerged friction stir welded Ti-6Al-4V alloy
	Wu, LH; Zhang, H; Zeng, XH; Xue, P; Xiao, B; Ma, ZY; Ma, ZY (reprint author), Chinese Acad Sci, Shenyang Natl Lab Mat Sci, Inst Met Res, Shenyang 110016, Liaoning, Peoples R China.
	2018-03-01
发表期刊	SCIENCE CHINA-MATERIALS
ISSN	2095-8226
卷号	61 期号:3 页码:417-423
摘要	The superplastic forming of Ti alloy welds has great application prospects in producing integrated components. However, the nugget zone (NZ) of the Ti alloy welds, produced by fusion welding or conventional friction stir welding (FSW), consists of lamellar microstructure, which exhibits either low superplasticity or high superplastic temperautre and low strain rate. As a result, the NZ plays a leading role in hindering the superplastic forming of the whole welds. In this study, submerged friction stir welding (SFSW) was conducted in Ti-6Al-4V alloy for the first time, and a defectfree weld with the NZ consisting of a strip microstructure was obtained. The NZ exhibited a low-temperature superplasticity at 600 degrees C, which was the lowest superplastic temperature ever reported in the Ti alloy welds. Besides, at 800 degrees C, the NZ showed high strain rate (3x10(-2) s(-1)) superplasticity and a largest elongation of 615% at 1x10(-3) s(-1). Compared to conventional FSW joints, the NZ of SFSW joint exhibited a much lower flow stress and a decrease in optimal superplastic temperature by 100 degrees C. This is mainly attributed to the easy globularization of the strip microstructure, enhancing the ability of grain/phase boundary sliding.; The superplastic forming of Ti alloy welds has great application prospects in producing integrated components. However, the nugget zone (NZ) of the Ti alloy welds, produced by fusion welding or conventional friction stir welding (FSW), consists of lamellar microstructure, which exhibits either low superplasticity or high superplastic temperautre and low strain rate. As a result, the NZ plays a leading role in hindering the superplastic forming of the whole welds. In this study, submerged friction stir welding (SFSW) was conducted in Ti-6Al-4V alloy for the first time, and a defectfree weld with the NZ consisting of a strip microstructure was obtained. The NZ exhibited a low-temperature superplasticity at 600 degrees C, which was the lowest superplastic temperature ever reported in the Ti alloy welds. Besides, at 800 degrees C, the NZ showed high strain rate (3x10(-2) s(-1)) superplasticity and a largest elongation of 615% at 1x10(-3) s(-1). Compared to conventional FSW joints, the NZ of SFSW joint exhibited a much lower flow stress and a decrease in optimal superplastic temperature by 100 degrees C. This is mainly attributed to the easy globularization of the strip microstructure, enhancing the ability of grain/phase boundary sliding.
部门归属	[wu, lihui ; zhang, hao ; zeng, xianghao ; xue, peng ; xiao, bolv ; ma, zongyi] chinese acad sci, shenyang natl lab mat sci, inst met res, shenyang 110016, liaoning, peoples r china
关键词	Lamellar Microstructure Titanium Joint Deformation Evolution Behavior Surface Nugget Zone
学科领域	Materials Science, Multidisciplinary
资助者	National Natural Science Foundation of China [51471171, 51601194, 51331008]
收录类别	SCI
语种	英语
WOS记录号	WOS:000428198700009
引用统计	被引频次：9[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/321006/79452
专题	中国科学院金属研究所
通讯作者	Ma, ZY (reprint author), Chinese Acad Sci, Shenyang Natl Lab Mat Sci, Inst Met Res, Shenyang 110016, Liaoning, Peoples R China.
推荐引用方式 GB/T 7714	Wu, LH,Zhang, H,Zeng, XH,et al. Achieving superior low temperature and high strain rate superplasticity in submerged friction stir welded Ti-6Al-4V alloy[J]. SCIENCE CHINA-MATERIALS,2018,61(3):417-423.
APA	Wu, LH.,Zhang, H.,Zeng, XH.,Xue, P.,Xiao, B.,...&Ma, ZY .(2018).Achieving superior low temperature and high strain rate superplasticity in submerged friction stir welded Ti-6Al-4V alloy.SCIENCE CHINA-MATERIALS,61(3),417-423.
MLA	Wu, LH,et al."Achieving superior low temperature and high strain rate superplasticity in submerged friction stir welded Ti-6Al-4V alloy".SCIENCE CHINA-MATERIALS 61.3(2018):417-423.