X80管线钢与氢环境相容性试验研究

针对在高压气相氢环境下开展的X80管线钢慢应变速率拉伸试验、断裂韧性试验、疲劳裂纹扩展速率试验，分析了不同氢分压对X80管线钢力学性能、疲劳性能及断口形貌的影响规律。研究结果表明，氢分压是影响材料氢脆和疲劳性能的重要因素，随着氢分压的增加，X80管线钢的氢脆敏感性显著增大，缺口疲劳试样的疲劳循环次数显著降低，断口韧窝间出现典型的具有小平面和撕裂棱的准解理特征脆性断裂形貌，疲劳裂纹扩展速率急剧增加，增加了管道失效风险。研究结果可为高强度输送掺氢天然气管道工程临界评估提供参考。

Study on Compatibility of X80 Pipeline Steel with Hydrogen Environment

Based on the slow strain rate tensile test, fracture toughness test and fatigue crack growth rate test of X80 pipeline steel under high pressure vapor phase hydrogen environment, the influence of different hydrogen partial pressure on the mechanical properties, fatigue properties and fracture morphology of X80 pipeline steel was analyzed. The results show that the hydrogen partial pressure is an important factor affecting the hydrogen embrittlement and fatigue properties of the material. As the hydrogen partial pressure increases, the hydrogen embrittlement sensitivity of X80 pipeline steel gradually increases, and the number of fatigue cycles of notched fatigue specimens decreases significantly. Typical quasi?issolution characteristic brittle fracture morphology with small planes and tearing ribs appears between the fracture toughness nests, and the fatigue crack expansion rate increases sharply, which increases the risk of pipe failure. The results of the study can provide reference for engineering critical evaluation of high strength pipeline for transporting hydrogen?oped natural gas.