Microstructure and Mechanical Properties of X70 Pipeline Steel with High H₂S Resistance

Abstract:

Anti-H₂S X70 pipeline steel was developed. The microstructure of X70 pipeline steel was studied by the analysis of OM, SEM and TEM. The precipitation behavior was discussed. The comprehensive mechanical properties, HIC and SCC performance were systematically studied. The results indicated that the microstructure of the experimental steel was mainly acicular ferrite and granular bainite. The second phase precipitates dispersedly distributed in the matrix. The experimental steel possessed excellent strength, plasticity, low temperature toughness and low yield ratio. And therefore, the X70 pipeline steel in the study is suitable for sour service with the high strength, excellent toughness and low HIC&SSC susceptibility.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 755-760
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.755
• Online since: April 2015
• Authors: Jing Li, Xiu Hua Gao*, Yong Lu, Lin Xiu Du
• Keywords: Acicular Ferrites, Corrosion-Resistant, Mechanical Properties, Microstructure, X70 Pipeline Steel

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