Relationship between microstructure and hydrogen induced cracking behavior in a low alloy pipeline steel

• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2017,（12）
• 页码范围: 1504-1512
• 页数: 9页
• 语种: 英文

摘要

Hydrogen induced cracking (HIC) behaviors of a high strength pipeline steel with three different microstructures,granular bainite & lath bainite (GB + LB),granular bainite & acicular ferrite (GB +AF),and quasi-polygonal ferrite (QF),were studied by using corrosion experiment based on standard NACE TM 0284.The HIC experiment was conducted in hydrogen sulfide (H2S)-saturated solution.The experimental results show that the steel with GB + AF and QF microstructure present excellent corrosion resistance to HIC,whereas the phases of bainite lath and martensite/austenite in LB + GB microstructure are responsible for poor corrosion resistance.Compared with ferrite phase,the bainite microstructure exhibits higher strength and crack susceptibility of HIC.The AF + GB microstructure is believed to have the best combination of mechanical properties and resistance to HIC among the designed steels.