氢的存在会导致管道力学性能劣化,对海底管道安全产生威胁。考虑输氢海底管道的主要力学性能包括拉伸性能、断裂韧度和疲劳裂纹扩展等,通过研究氢脆相关的主要因素,讨论输氢海底管道材料选择的技术要求。研究结果表明:1)氢对钢的拉伸性能影响主要表现为降低钢的延展性;2)考虑到焊缝的氢脆风险,在成本允许条件下,宜选择无缝钢管;3)晶粒度和晶相组织均匀度优化后的钢具有更好的抗疲劳性能；4)钢的氢致疲劳裂纹扩展速率增加不可避免，疲劳裂纹扩展速率除与材料断裂韧度、强度、微观组织等固有性能相关外,实际载荷对裂纹扩展也有重要影响。因此，在保证材料有充足的延展性和较高的断裂韧度的前提下,还应考虑降低应力水平,以提高裂纹启动所需的应力强度因子和裂纹扩展Ⅲ阶段的疲劳断裂韧度,延迟材料的疲劳裂纹扩展和增长疲劳寿命。

The existence of hydrogen will cause deterioration in pipeline mechanical properties and threaten the safe operation of subsea pipelines. This paper considers the main mechanical properties required by the hydrogen subsea pipeline, including tensile performance, fracture toughness, and fatigue crack growth. By studying the main factors related to the hydrogen embrittlement, materials selection of hydrogen subsea pipeline has been discussed in details. The study results show that:1) The hydrogen impact on steel’s tensile properties is mainly ductility decrease;2) Considering the risk of hydrogen embrittlement for welds, seamless steel pipe is recommended if cost allows;3) optimization on grain size and micro structure uniformity will increase the fatigue resistance of line pipe;4) The increasing of steel’s fatigue crack growth rate induced by hydrogen is inevitable. The fatigue crack growth rate is not only related to the inherent properties such as fracture toughness, strength and microstructure, but also influenced by the actual stress level. Therefore, on the premise of ensuring sufficient ductility and high fracture toughness of the material, it is necessary to reduce the stress level to improve the stress intensity factor required for crack initiation and fracture toughness at stage Ⅲ of fatigue crack propagation, and to delay the crack growth and increase the fatigue life of the material.