氢气输送用L360MH钢级HFW管材开发与抗氢脆性能研究

Development and Research on Hydrogen Brittleness Resistance of L360MH HFW Welded Pipe for Hydrogen Transport

采用低碳低锰微合金化设计、高洁净炼钢和控轧控冷技术制备热轧卷板,通过高频焊(HFW)工艺和热处理技术制造出了抗氢脆性能优异的L360MH钢级HFW氢气输送管材。试验检测表明,在6.3 MPa氢气环境下,HFW管体和焊缝缺口试样均具有优异的抗氢脆性能,慢拉伸强度损失率分别为0.4%和4.2%,断面收缩率损失率分别为3.2%和1.2%,断裂韧性K_(IH)分别为236 MPa·m^(1/2)和210 MPa·m^(1/2),断口呈现韧性断裂;裂纹扩展速率差别不大,但相比氮气环境均快了10倍左右。将L360MH钢级Φ406.4 mm×10.8 mm HFW焊管充氢6.3 MPa,100天后检测其力学性能,其强度、韧性、塑性等各项指标优异,满足GB/T 9711—2023和ASME B31.12—2023要求。

The hot rolled coil of L360MH steel grade HFW hydrogen transport pipe,which exhibits excellent resistance to hydrogen brittleness,is manufactured using a low carbon and low manganese micro alloying design.This is achieved through the implementation of high clean steel making techniques as well as controlled rolling and cooling technology.The manufacturing process involves high frequency welding(HFW)and heat treatment technology.Test results demonstrate excellent resistance to hydrogen embrittlement in HFW tube body and weld notch samples under a 6.3 MPa hydrogen environment,with slow rates of tensile strength loss at 0.4%and 4.2%,and section shrinkage loss rates at 3.2%and 1.2%,respectively.Fracture toughness values K_(IH)were measured at 236 MPa·m^(1/2)and 211 MPa·m^(1/2),respectively,indicating ductile fracture behavior.Additionally,the crack propagation rate is approximately ten times faster than that observed in nitrogen environments.The L360MH steel gradeΦ406.4 mm×10.8 mm HFW welded pipe was subjected to a hydrogen filling pressure of 6.3 MPa,and its mechanical properties were evaluated after a period of 100 days.The results demonstrated excellent strength,toughness,plasticity,and other performance indicators that fully comply with the requirements specified in GB/T 9711—2023 as well as ASME B31.12—2023.