不同应力三轴度下电化学充氢对X80管线钢性能影响  

Effect of Electrochemical Hydrogen Charging on Properties of X80 Pipeline Steel under Different Stress Triaxialities

作　　者：封辉 朱兴华 FENG Hui;ZHU Xinghua(CNPC Tubular Goods Research Institute Co.,Ltd.,Xi′an 710077,China;State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials,Xi′an 710077,China;Yantai Lubao Steel Pipe Co.,Ltd.,Yantai 264000,Shandong,China)

机构地区：[1]中国石油集团工程材料研究院有限公司,西安710077 [2]石油管材及装备材料服役行为与结构安全国家重点实验室,西安710077 [3]烟台鲁宝钢管有限责任公司,山东烟台264000

出　　处：《焊管》2023年第9期9-13,共5页Welded Pipe and Tube

基　　金：中国石油天然气集团公司科学研究与技术开发项目“中长距离管道纯氢/掺氢输送关键技术研究”(项目编号2021DJ5002);陕西省氢能产业重点专项“氢气输送管道应用关键技术研究”(项目编号2021LLRH-09)。

摘　　要：采用缺口圆棒拉伸试验、电化学充氢和扫描电镜观察等方法研究了不同应力三轴度下氢对X80管线钢性能影响。结果表明,对于初始应力三轴度相同的X80管线钢,电化学充氢降低了材料的缺口试样抗拉强度和断面收缩率,同时随着充氢时间延长,强度和断面收缩率降低越明显。缺口拉伸试样初始应力三轴度由1.02升高为1.25,材料的缺口试样抗拉强度和断面收缩率降低,当充氢8 h,材料抗拉强度降低幅度由1.3%升高至5.5%;充氢24 h条件下,材料抗拉强度降低幅度随应力三轴度升高,由6.6%升高至9.9%。同时随着应力三轴度不断升高,材料缺口位置应力集中程度越高,氢更容易在材料表面和内部扩散聚集,造成不可逆氢损伤,因而材料的抗拉强度降幅增大。The influence of hydrogen on the mechanical properties of X80 pipeline steel under different stress triaxialities was studied by notched round bar tensile test,electrochemical hydrogen charging and scanning electron microscopy examination.The results show that for X80 pipeline steel with the same initial stress triaxiality,electrochemical hydrogen charging reduced the notch tensile strength and the reduction of shearing area.The moment the hydrogen charging time has prolonged,the strength and reduction of shearing area has decreased more significantly.The initial stress triaxiality of the notched tensile specimen increased from 1.02 to 1.25,resulting in a decrease in the notched tensile strength and reduction of shearing area of the material.The material's tensile strength decreases from 1.3%to 5.5%after 8 h hydrogen charging.The decrease in tensile strength of the X80 pipeline steel material increases from 6.6%to 9.9%with the increase of stress triaxiality after 24 h hydrogen charging.The increase in stress triaxiality results in a higher degree of stress concentration at the X80 pipeline steel material notch,making it easier for hydrogen to diffuse and accumulate on the surface and inside the X80 pipeline steel material,causing irreversible hydrogen damage,thus resulting in an increase in the decrease in tensile strength of the material.

关 键 词：X80管线钢 电化学充氢 应力三轴度 缺口拉伸 

分 类 号：TG142.1[一般工业技术—材料科学与工程]