Effect of Pre-Tension on the Fatigue Fracture of Under-Aged 7N01 Aluminum Alloy Plate

doi:10.11900/0412.1961.2021.00017

IMR OpenIR

	Effect of Pre-Tension on the Fatigue Fracture of Under-Aged 7N01 Aluminum Alloy Plate
	Tian Ni 1,2; Shi Xu 1; Liu Wei 1; Liu Chuncheng 3; Zhao Gang 1,2; Zuo Liang 2,4
通讯作者	Tian Ni(tiann@atm.neu.edu.cn)
	2022-06-11
发表期刊	ACTA METALLURGICA SINICA
ISSN	0412-1961
卷号	58 期号:6 页码:760-770
摘要	7N01 aluminum alloy is the main load-bearing structure material for bullet train bodies due to its high specific strength, high specific stiffness, good magnetic-shielding ability, strong corrosion resistance, and good formability and weldability. The fatigue performance of materials and components used in bullet trains determines their security. It is unavoidable that there is pre-deformation during the assembly process of aluminum alloy components, which will influence the active service and fatigue performance of the aluminum alloy. It is important not only to clarify the relationship between pre-deformation and fatigue performance but also to reveal the mechanism of pre-deformation on the fatigue fracture of 7N01 aluminum alloy, to ensure the security of the bullet train. In this study, the effect of pre-tensile deformation on the fatigue property, fatigue fracture initiation, and fatigue crack propagation characteristics of a commercial 7N01 aluminum alloy plate at under-aged conditions was studied using tensile and fatigue tests combined with microstructure analysis. As the pre-tensile deformation increased to 20%, the results showed that the shape, size, number, distribution of second phase particles, as well as the size and morphology of thin strips grain of under-aged 7N01 aluminum alloy plate were almost the same. However, the under-aged 7N01 aluminum alloy plate has a significant strain-hardening effect after pre-tensile at room temperature, with the yield strength, tensile strength, and hardness increased from 181 MPa, 233 MPa, and 95 HV (without pre-tensile deformation) to 254 MPa, 271 MPa, and 117 HV (after 20% pretensile deformation), while the elongation decreased from 23.2% to 5.2%. Under the 175 MPa pulsating tensile load condition (stress ratio R = 0), the overall fatigue life of the under-aged 7N01 aluminum alloy plate first reduced, then prolonged, and then decreased as pre-tensile deformation increased. Without pre-tensile deformation, the fatigue life of under-aged 7N01 aluminum alloy plate is about 6.06 x 10(5) cyc, and when prolonged by about 75%, it reaches about 1.06 x 10(6) cyc after 5% pre-tensile deformation. However, the fatigue life of the under-aged 7N01 aluminum alloy plate is decreased to 4.21 x 10(5) and 2.89 x 10(5) cyc after 3% and 20% pre-tensile deformation, respectively. The evenly distributed highdensity dislocations or dislocation cells resulted in 5%-16% pre-tensile deformation in the under-aged 7N01 aluminum alloy plate, which can prolong the fatigue life of the alloy plate by over 23%.
关键词	7N01 aluminum alloy plate pre-tensile deformation under-aged dislocation fatigue
资助者	National Natural Science Foundation of China ; Fundamental Research Funds for the Central Universities of China ; Natural Science Foundation of Liaoning Province
DOI	10.11900/0412.1961.2021.00017
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China[51871043] ; Fundamental Research Funds for the Central Universities of China[180212010] ; Natural Science Foundation of Liaoning Province
WOS研究方向	Metallurgy & Metallurgical Engineering
WOS类目	Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000799262400004
出版者	SCIENCE PRESS
引用统计	被引频次：3[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/321006/174108
专题	中国科学院金属研究所
通讯作者	Tian Ni
作者单位	1.Northeastern Univ, Sch Mat Sci & Engn, Shenyang 110819, Peoples R China 2.Northeastern Univ, Key Lab Anisotropy & Texture Mat, Minist Educ, Shenyang 110819, Peoples R China 3.Northeastern Univ, Engn Training Ctr, Shenyang 110819, Peoples R China 4.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Tian Ni,Shi Xu,Liu Wei,et al. Effect of Pre-Tension on the Fatigue Fracture of Under-Aged 7N01 Aluminum Alloy Plate[J]. ACTA METALLURGICA SINICA,2022,58(6):760-770.
APA	Tian Ni,Shi Xu,Liu Wei,Liu Chuncheng,Zhao Gang,&Zuo Liang.(2022).Effect of Pre-Tension on the Fatigue Fracture of Under-Aged 7N01 Aluminum Alloy Plate.ACTA METALLURGICA SINICA,58(6),760-770.
MLA	Tian Ni,et al."Effect of Pre-Tension on the Fatigue Fracture of Under-Aged 7N01 Aluminum Alloy Plate".ACTA METALLURGICA SINICA 58.6(2022):760-770.