Characterization of the Welded-Joint of High-Strength High-Toughness Seamless Steel Pipe under High-Cycle Fatigue Condition

Abstract:

The welded joint of a S890QL grade steel pipes containing 1.2% Ni have been prepared to characterize the use performance under high cycle fatigue test. It has been found that the fatigue strength of the welded joint is 290MPa with a fatigue life of more than 10 million cycles, and the obtained Basquin equation is σa=488*(2N)-0.02758 . It is found that the steel exhibits the whole bainite microstructure when the cooling rate is less than 1°C/s. The welded joint is divided into the weld zone, the coarse grain zone, the fine grain zone, the softening zone and the matrix. The fine grain characteristic in the welded area determines the good anti fatigue performance of the investigated steel.

• Periodical: Materials Science Forum (Volume 896)
• Pages: 202-208
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.896.202
• Online since: March 2017
• Authors: Qing Chao Tian*, Xian Ping Dong, Hai Chao Cui, Ke Xu
• Keywords: Fatigue Performance, High-Strength High-Toughness Steel, Seamless Steel Pipe, Welded Joint

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