管线钢合金元素和显微组织对钢的抗硫应力腐蚀的影响

Effects by Alloy Element and Microstructure of Linepipe Steel on its SSC Resistance

叙述了合金元素、制备工艺及显微组织对钢的抗SSC性能和HIC能力的影响。认为:在设计钢的化学成分时,可根据不同元素对其SSC性能的影响,选取多种元素同时添加以改善钢的抗SSC性能;与普通高温回火相比,在较低温度下长时间回火或双次回火可能会更大程度地提高马氏体组织材料的抗SSC性能;在马氏体组织中引入铁素体,可进一步提高材料的抗SSC性能。此外,还可以尝试在材料中加入适量的Cu元素,再通过临界淬火+回火的方法得到回火索氏体和铁素体复相组织,使材料具有较高的强度和较好的抗SSC性能。

Summarized here in the paper are the effects by the alloy elements,the manufacturing process and the microstructure of the steel on the SSC and HIC resistances thereof.It is regarded as follows.When designing the steel chemical composition,according to the effect by deferent chemical element on the SSC resistance of the steel,multi elements can be chosen,and added into the steel at the same time to improve the steel’s SSC resistance.Compared with the effect by the normal high temperature tempering process,the long-time,low-temperature tempering process or the double tempering process is possible to further improve the SSC resistance of the martensitic structured steel;and the SSC resistance of the steel will be also further enhanced by means of introducing the ferrite into the martensitic structure.Moreover it is worth trying to add proper amount of Element Cu into the steel and then conduct the critical quenching+the normal tempering process to get tempered sorbit-ferrite composite structure in a bid to make the steel have better strength and SSC resistance.