Microstructural and mechanical characterization of welded joints on innovative high-strength steels

被引:0
作者
Holovenko, O. [1 ]
Lenco, M. G. [1 ]
Pastore, E. [1 ]
Pinasco, M. R. [1 ]
Matteis, P. [2 ]
Scavino, G. [2 ]
Firrao, D. [2 ]
机构
[1] Univ Genoa, Dipartimento Chim & Chim Ind, Genoa, Italy
[2] Politecn Torino, Dipartimento Sci Applicata Tecnol, Turin, Italy
来源
METALLURGIA ITALIANA | 2013年 / 03期
关键词
Steel; Fatigue; Welding; Automotive; AUSTENITIC STEEL; TWIP STEELS;
D O I
暂无
中图分类号
TF [冶金工业];
学科分类号
0806 ;
摘要
The car-bodies are more and more frequently constructed with innovative high-strength steels, both to reduce the vehicles weight and to improve the passenger safety. The car-body parts are cold formed from steel sheets (manufactured by continuous casting, hot and cold rolling, and continuous heat treatment), and assembled by resistance spot welding or less frequently, by laser welding The welded joints obtained with the latter methods on two high-strength steels, with similar ultimate tensile strength, are examined here. An innovative, 18% Mn, austenitic TWIP steel, which exhibit a very good combination of strength and ductility, is compared with a widely used DP steel, which consists of ferrite and martensite obtained by intercritical heat treatment and fast cooling The size and shape, defects, and microstructure of each welded joint are evidenced by metallographic examinations. Moreover, the tensile properties and the stress-life fatigue behavior of both as-received and welded specimens are compared. The fatigue strength exhibit a sharp reduction after the resistance spot welding, whereas laser welding has a much smaller effect.
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页码:3 / 12
页数:10
相关论文
共 14 条
[11]  
Speich G. R., 1990, ASM HDB, V1, p424
[12]  
Williams N.T., 1993, ASM Handb, V6, P226
[13]   Spatio-temporal characteristics of the Portevin-Le Chatelier effect in austenitic steel with twinning induced plasticity [J].
Zavattieri, P. D. ;
Savic, V. ;
Hector, L. G., Jr. ;
Fekete, J. R. ;
Tong, W. ;
Xuan, Y. .
INTERNATIONAL JOURNAL OF PLASTICITY, 2009, 25 (12) :2298-2330
[14]   Stress intensities at spot welds [J].
Zhang, SC .
INTERNATIONAL JOURNAL OF FRACTURE, 1997, 88 (02) :167-185