Achieving superior mechanical and corrosion properties in medium-thickness Ti-6Al-4 V alloy joints by back heating assisted friction stir welding below β-phase transformation temperature

doi:10.1016/j.matchar.2024.114391

IMR OpenIR

	Achieving superior mechanical and corrosion properties in medium-thickness Ti-6Al-4 V alloy joints by back heating assisted friction stir welding below β-phase transformation temperature
	Cong, S.1,2; Wu, L. H.1,2; Wang, Z. W.1,2; Li, N.1,2; Zhu, Z.3; Wang, F. F.4; Zhang, X.5; Wang, K.5; Xue, P.1,2; Ni, D. R.1,2; Xiao, B. L.1,2; Ma, Z. Y.1,2
通讯作者	Wu, L. H.(lhwu@imr.ac.cn) ; Wang, Z. W.(zwwang16b@imr.ac.cn)
	2024-11-01
发表期刊	MATERIALS CHARACTERIZATION
ISSN	1044-5803
卷号	217 页码:11
摘要	The equiaxed microstructure formed below the beta-phase transition point of Ti alloys generally exhibits an excellent balance of mechanical properties and corrosion resistance. However, this desirable microstructure is impossible to be obtained in fusion welded joints but is prospective to be achieved by the solid-state friction stir welding (FSW) technique. Unfortunately, it generally generates bottom defects and severe tool wear in medium- thickness Ti alloy joints when conventional FSW was conducted below the beta-phase transition point. In this study, 6 mm thick Ti-6Al-4 V plates were joined by both the conventional FSW and back heating assisted FSW (BHAFSW). Defects caused by significant tool wear and bottom phase transition differences occurred in the conventional FSW. It was found that the hardness difference between the base material (BM) and the tool increased to 35.6 % from 500 degrees C to 900 degrees C. The back heating (150 degrees C) was used to control welding temperatures remaining the 900 degrees C, thus largely reducing the tool wear by increasing the hardness difference. In addition, the back temperature compensation increased the bottom temperature and controlled the phase transition position from the bottom to the middle of the joint. The shoulder pressure contributed to the compression of the defects, and the defects were eliminated by increasing the pressure at the phase transition position. A significantly refined equiaxed microstructure with an average grain size of similar to 0.9 mu m was achieved below the beta-phase transition temperature in the stir zone via back heating assisted FSW, while a bimodal structure with an average grain size of 3.5 mu m was formed near the beta-phase transition temperature. Inconspicuous reduction of the strength was detected for the joints (98 % of the BM) which possess equiaxed microstructures, and the corrosion resistance of the joints was enhanced compared to the BM. This superior synergy of mechanical and corrosion properties exceeded the majority of Ti alloy joints previously reported. This study provided an effective method for obtaining medium-thickness Ti alloy joints with ultrafine equiaxial structures with superior mechanical properties and corrosion resistance.
关键词	Ti alloys Friction stir welding Back heating assisting welding Microstructure Mechanical property Corrosion resistance
资助者	National Natural Science Foundation of China ; Youth Innovation Promotion Association of the Chinese Academy of Sciences ; Shi Changxu Innovation Center for Advanced Materials
DOI	10.1016/j.matchar.2024.114391
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[52171057] ; National Natural Science Foundation of China[52301067] ; Youth Innovation Promotion Association of the Chinese Academy of Sciences[2021193] ; Youth Innovation Promotion Association of the Chinese Academy of Sciences[Y2021061] ; Shi Changxu Innovation Center for Advanced Materials[SCXKFJJ202210]
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering ; Materials Science, Characterization & Testing
WOS记录号	WOS:001334994100001
出版者	ELSEVIER SCIENCE INC
引用统计	被引频次：1[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/321006/190802
专题	中国科学院金属研究所
通讯作者	Wu, L. H.; Wang, Z. W.
作者单位	1.Chinese Acad Sci, Inst Met Res, Shi Changxu Innovat Ctr Adv Mat, 72 Wenhua Rd, Shenyang 110016, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, 72 Wenhua Rd, Shenyang 110016, Peoples R China 3.Shenyang Aerosp Univ, Coll Mat Sci & Engn, 37 Daoyi South Ave, Shenyang 110136, Peoples R China 4.China Acad Launch Vehicle Technol, Beijing 100076, Peoples R China 5.Capital Aerosp Machinery Co Ltd, 2 Jingbei East Rd, Beijing 100076, Peoples R China
推荐引用方式 GB/T 7714	Cong, S.,Wu, L. H.,Wang, Z. W.,et al. Achieving superior mechanical and corrosion properties in medium-thickness Ti-6Al-4 V alloy joints by back heating assisted friction stir welding below β-phase transformation temperature[J]. MATERIALS CHARACTERIZATION,2024,217:11.
APA	Cong, S..,Wu, L. H..,Wang, Z. W..,Li, N..,Zhu, Z..,...&Ma, Z. Y..(2024).Achieving superior mechanical and corrosion properties in medium-thickness Ti-6Al-4 V alloy joints by back heating assisted friction stir welding below β-phase transformation temperature.MATERIALS CHARACTERIZATION,217,11.
MLA	Cong, S.,et al."Achieving superior mechanical and corrosion properties in medium-thickness Ti-6Al-4 V alloy joints by back heating assisted friction stir welding below β-phase transformation temperature".MATERIALS CHARACTERIZATION 217(2024):11.