Thermal cycles, microstructures and mechanical properties of AA7075-T6 ultrathin sheet joints produced by high speed friction stir welding

doi:10.1016/j.matchar.2022.111873

	Thermal cycles, microstructures and mechanical properties of AA7075-T6 ultrathin sheet joints produced by high speed friction stir welding
	Ni, Yu 1,2; Liu, Yuanhao 2; Zhang, Pengxian 1; Huang, Jiankang 1; Yu, Xiaoquan 2
刊名	MATERIALS CHARACTERIZATION
	2022-05-01
卷号	187
关键词	High speed FSW Ultrathin sheet Pinless tool Thermal cycle Microstructure Mechanical property
ISSN号	1044-5803
DOI	10.1016/j.matchar.2022.111873
英文摘要	0.5 mm thick AA 7075-T6 ultrathin sheets were butt jointed by conventional friction stir welding (C-FSW) and high speed friction stir welding (HS-FSW) under a constant rotational speed (w)/welding speed (v) ratio of 6.67 rad/mm using a pinless tool. In this study, the conventional w of 2000 rpm and conventional v of 300 mm/min were adopted by C-FSW, and the high w of 8000 rpm and high v of 1200 mm/min were adopted by HS-FSW. Compared with C-FSW, HS-FSW presented a fast heating and cooling rate thermal characteristic with a slightly higher peak temperature and significantly shorter elevated-temperature exposure time. Kissing bond defect was appeared in the weld bottom for C-FSW. While, no obvious defect was found in the weld obtained by HS-FSW. Compared with C-FSW, the proportion of deformed grains in the center of nugget zone (NZ) fabricated by HS-FSW was increased. For the joint fabricated by HS-FSW, the upper NZ was dominated by recrystallized grains, and the lower NZ was dominated by deformed grains. The ultimate tensile strength of the joint fabricated by HS-FSW can reach 87% of base metal (BM), and its elongation, yield strength and ultimate tensile strength were increased by 58.8%, 23.3% and 22.8% respectively compared with C-FSW. Both the joints fractured in the center of the NZ. The joint fabricated by C-FSW broke due to the kissing bond defect. While the joint fabricated by HS-FSW may be broken due to the weld thickness reduction.
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
语种	英语
出版者	ELSEVIER SCIENCE INC
WOS记录号	WOS:000807680000001
内容类型	期刊论文
源URL	[http://ir.lut.edu.cn/handle/2XXMBERH/158653]
专题	材料科学与工程学院
作者单位	1.Lanzhou Univ Technol, State Key Lab Adv Proc & Recycling Nonferrous Met, Lanzhou 730050, Peoples R China; 2.Lanzhou Univ Technol, Sch Mat Sci & Engn, Lanzhou 730050, Peoples R China
推荐引用方式 GB/T 7714	Ni, Yu,Liu, Yuanhao,Zhang, Pengxian,et al. Thermal cycles, microstructures and mechanical properties of AA7075-T6 ultrathin sheet joints produced by high speed friction stir welding[J]. MATERIALS CHARACTERIZATION,2022,187.
APA	Ni, Yu,Liu, Yuanhao,Zhang, Pengxian,Huang, Jiankang,&Yu, Xiaoquan.(2022).Thermal cycles, microstructures and mechanical properties of AA7075-T6 ultrathin sheet joints produced by high speed friction stir welding.MATERIALS CHARACTERIZATION,187.
MLA	Ni, Yu,et al."Thermal cycles, microstructures and mechanical properties of AA7075-T6 ultrathin sheet joints produced by high speed friction stir welding".MATERIALS CHARACTERIZATION 187(2022).