摘要
利用扫描电子显微镜(SEM),透射电子显微镜(TEM)和电子背散射衍射技术(EBSD)研究了热处理工艺对Q125级ERW石油套管用钢中组织和性能的影响。结果表明,实验钢采用870℃淬火+500℃回火调质处理后,其组织为典型的回火索氏体,组织内含有100~150 nm的细化马氏体板条,板条内部存在两类亚结构,一类是对提升韧性有利的位错胞状亚结构,另一类是对强度贡献较大的高密度、相互缠结的位错亚结构;在此工艺条件下,使得Q125石油套管钢的屈服强度为950 MPa,抗拉强度985 MPa,伸长率为18%,0℃冲击功为58 J,具备良好的综合力学性能,满足API的标准对钢板的要求。
Influence of heat treatment on microstructure and mechanical properties of Q125 electric resistance welded(ERW) oil casing steel were studied by means of SEM,TEM and EBSD.The results show that the microstructure of Q125 tested steel is typical tempered sorbite retaining the morphology of martensite laths with width of 100-150 nm after it is quenched at 870 ℃and tempered at 500 ℃.Two types of sub-structure exist in the laths: one is dislocation cell structure which is of benefit to improving of toughness and the other is high density and tangled dislocation substructure which is favourable to improve the strength.Under the heat treatment,tested Q125 steel exhibits outstanding mechanical properties with yield strength of 950 MPa,tensile strength of 985 MPa,elongation of 18% and Charpy-V impact energy of 58 J at 0 ℃,which meet the standard of Q125 ERW oil casing steel.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2012年第5期81-84,共4页
Transactions of Materials and Heat Treatment
基金
国家科技重大专项(2011ZX05016-004)