摘要
通过改变环境箱中填充物的体积来获得不同的氢气体积/缺口试样表面积比值RV/S,使用疲劳寿命试验和扫描电镜研究了RV/S对管线钢氢气环境下疲劳寿命的影响,对输氢管道中气态氢分子自发分解成氢原子的氢脆理论进行了讨论。结果表明与氮气中相比,当RV/S从2.6 mL/mm2增加到24.4 mL/mm2时,X52管线钢环焊缝在高压氢环境下的疲劳寿命损失率从21.2%增加到57.2%,X52管线钢母材疲劳寿命损失率从2.1%增加到53.2%,X52管线钢环焊缝和母材疲劳寿命试验断口快速撕裂区韧窝面积明显减少,韧窝区裂纹和空洞等缺陷出现增加趋势。疲劳寿命试验过程中,氮气中早期疲劳裂纹萌生后出现裂纹止裂阶段,而当氢气体积/试样缺口表面积比为24.4 mL/mm2时,疲劳裂纹一旦萌生即不断扩展直至试样断裂。RV/S比值对X52管线钢在高压氢环境下的疲劳寿命循环次数存在着显著影响,试验结果为气态氢分子自发分解成氢原子的氢脆理论提供了试验数据支撑。
By varying the volume of filling material in the environmental chamber,different hydrogen volume/sample notch surface area ratios(Rv/s)were obtained.The fatigue life test and scanning electron microscopy(SEM)were used to study the effect of Rv/s ratio on the fatigue life of pipeline steel under hydrogen environment.The hydrogen embrittlement theory of spontaneous dissociation of gaseous hydrogen molecules into hydrogen atoms in hydrogen pipelines was discussed.Compared with nitrogen,when Rv/s increases from 2.6 mL/mm²to 24.4 mL/mm²,the fatigue life loss rate of X52 pipeline steel girth weld in high-pressure hydrogen environment increased from 21.2%to 57.2%,the fatigue life loss rate of X52 pipeline steel base material increased from 2.1%to 53.2%,the fracture surface toughness dimples in the fatigue life test rapid tearing zone of X52 pipeline steel girth weld and base environment reduced significantly;there was an increasing trend of defects such as cracks and voids in the ductile dimple area.During the fatigue life test,the crack stop propagating after the initiation of fatigue cracks in nitrogen.However,when the ratio of hydrogen volume to the surface area of the specimen notch was 24.4mL/mm’,the fatigue cracks continued to propagate once they initiated until the specimen fractured.The Rv/s ratio has a significant impact on the fatigue life cycle number of X52 pipeline steel in high-pressure hydrogen environment.The results provided experimental data support for the hydrogen embrittlement theory of spontaneous dissociation of gaseous hydrogen molecules into hydrogen atoms.
作者
宋卫臣
汪兵
李拔
贾书君
刘清友
SONG Weichen;WANG Bing;LI Ba;JIA Shujun;LIU Qingyou(Mechanical Equipment Design Institute,Sinopec Petroleum Engineering Corporation,Dongying 257000,Shandong,China;Department of Structural Steels,Central Iron and Steel Research Institute Co.,Ltd.,Beijing 100081,China)
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2024年第6期776-786,共11页
Journal of Iron and Steel Research
关键词
X52管线钢
氢气体积/试样缺口表面积比
输氢管道
疲劳寿命
氢脆
X52 pipeline steel
hydrogen volume/sample notch surface area ratio
hydrogen transportation pipe-line
fatigue life
hydrogen embrittlement
