文献类型：期刊文献

英文题名：Hydrogen-assisted fracture toughness degradation and failure mechanisms of X80 pipeline steel under high-pressure hydrogen

作者：Li, Xinfeng[1];Chen, Yan[2];Shan, Guangbin[3];Shen, Sicong[4];Liu, Mingxu[2];Qu, Dingrong[3];Cui, Yan[5,6];Zhang, Yong[7];Zhang, Jin[8]

机构：[1]Sun Yat Sen Univ, Sino French Inst Nucl Engn & Technol, Zhuhai 519082, Guangdong, Peoples R China;[2]State Adm Market Regulat, Technol Innovat Ctr Hydrogen Storage Transportat &, Chengdu 610000, Peoples R China;[3]SINOPEC Res Inst Safety Engn Co Ltd, State Key Lab Chem Safety, Qingdao 266000, Peoples R China;[4]Xian Shiyou Univ, Coll Mat Sci & Engn, Xian 710065, Peoples R China;[5]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[6]East China Univ Sci & Technol, Res Ctr Anal & Test, Shanghai 200237, Peoples R China;[7]Univ Sci & Technol Beijing, State Key Lab Adv Met & Mat, Beijing 100083, Peoples R China;[8]Beijing Normal Univ, Fac Arts & Sci, Zhuhai 519087, Peoples R China

年份：2026

卷号：266

外文期刊名：CORROSION SCIENCE

收录：;EI(收录号：20261620548100);WOS:【SCI-EXPANDED(收录号:WOS:001753466100001)】；

基金：The authors acknowledge support from Guangdong Basic and Applied Basic Research Foundation (2026A1515011627, 2026A1515011663, 2023A1515240074), Open Project of Technology Innovation Center of Hydrogen Storage-Transportation and Fueling Equipments, State Administration for Market Regulation (TICHE2025002), Open Project of State Key Laboratory of Chemical Safety (SKLCS-2024009), State Key Laboratory for Advanced Metals and Materials, Grant No. 2025-Z05) . S. Shen acknowledge support from the Natural Science Foundation of Shaanxi Province of China (2025JC-YBMS-498) .

语种：英文

外文关键词：Hydrogen embrittlement; Fracture toughness; Plastic zone; X80 steel

摘要：Fracture toughness is a critical fracture mechanics parameter for assessing the structural integrity and safety of hydrogen transportation pipeline steels. In combination with the single-specimen compliance method, microhardness testing, secondary ion mass spectrometry, and fractographic analysis, this study systematically investigates the effects of hydrogen pressure on the elastic-plastic fracture toughness and failure mechanisms of X80 pipeline steel. The results show that compared with the fracture toughness in air (319.55 MPa m1-2), hydrogen markedly degrades the fracture toughness of the steel, i.e., 132.32 MPa m1-2 at 2.4 MPa H2, 117.94 MPa m1-2 at 6.3 MPa H2, and 111.91 MPa m1-2 at 12 MPa H2, respectively. For pipeline steels, the influence of hydrogen on fracture toughness exhibits a distinct two-stage behavior, comprising a low-pressure regime with strong dependence and a high-pressure regime with weak dependence, with a critical hydrogen pressure (Pcri) of approximately 7.5 MPa. This quantitative relationship can be described as KIC = 92.34 - ( 159.11 & lowast; 0.44PH2). The pressure dependence of fracture toughness is closely associated with the coupled effects of hydrogen concentration at the crack tip, local plastic deformation, and the size of the plastic zone. Below the Pcri, hydrogen enrichment at the crack tip strongly suppresses local plastic deformation, leading to a rapid contraction of the crack-tip plastic zone and a sharp decrease in fracture toughness. Above the Pcri, the crack-tip hydrogen concentration approaches a quasi-saturated state and the plastic zone size stabilizes at a lower bound, resulting in a plateau-like behavior. In addition, with increasing hydrogen pressure (0-12 MPa), the crack propagation direction gradually changes from approximately 45 degrees to about 30 degrees, and eventually approaches 0 degrees. This transition is mainly attributed to the shift in the hydrogen-assisted cracking mechanism from the maximum shear stress criterion to the maximum principal stress criterion.