低碳-低锰系油井套管用钢抗硫化氢应力腐蚀开裂性能

 对621MPa(90ksi)级抗硫化氢腐蚀油井套管用钢的合金设计、热处理工艺以及组织和性能关系进行了研究，分别设计了0.08C-0.8Mn和0.20C-0.8Mn 2种低碳-低锰试验钢，并重点研究了经调质处理后试验钢的位错、析出物和碳化物对SSCC性能的影响。研究结果表明，采用低碳-低锰，结合Nb、V、Ti和B的微合金设计，通过适当的调质热处理工艺可以获得优良的力学性能、韧性和抗硫化氢应力腐蚀开裂性能，满足相关标准的要求。研究结果还表明，不共平面的位错群、细小的析出物以及弥散的高球化率碳化物，可以使钢具有很好的抗硫化氢应力腐蚀开裂性能。

Hydrogen Sulfide Resistant Stress Corrosion Cracking of Low C-Mn Steels for Oil Well Casing

Alloy design, heat treatment process and microstructure and properties relationship of 621MPa(90ksi) grade oil well casing steels of H2S resistant corrosion were studied. Such two kinds as 0.08C-0.8Mn and 0.20C-08Mn of low C-Mn tested steels were designed, respectively. And the effect of dislocation, precipitation and carbide of tested steels after heat treatment on SSCC performance was investigated. The results show that the low C-Mn and Nb-V-Ti-B micro-alloy design has excellent mechanical properties, toughness and resistance to H2S stress corrosion cracking performance through proper quenching and tempering heat treatment process, to meet the requirements of the relevant standards. The results also show that the un-coplanar dislocation group, fine precipitates and dispersive high sphericity carbide would be beneficial to excellent hydrogen sulfide stress corrosion cracking resistance.