回火温度对一种新型石油套管钢力学性能的影响

Effect of tempering temperature on mechanical properties of the novel oil casting steel

对一种新型石油套管钢的热处理工艺进行了研究。通过组织观察和力学性能测试等手段,发现其最优的热处理制度为：920℃×60 min水淬＋590~610℃×120 min（水冷）回火的调质热处理工艺。经调质处理后,获得均匀稳定的回火索氏体组织,断口呈韧性断裂,具有较好的综合力学性能,抗拉强度可达882~916 MPa,屈服强度可达798~813 MPa,硬度可达26.2~27.8 HRC,冲击功53~83 J,伸长率可达21%~22%。

The heat treatment process of a novel oil casting steel was studied. The optimum heat treatment process is obtained by microstructure observation and mechanical property tests,which is water quenching at 920 ℃ for 60 min and tempering at 590-610 ℃ for120 min（ water cooling）. After quenching and tempering,uniform and stable tempered sorbite of the steel is obtained and ductile fracture is dimple,and the comprehensive mechanical properties of the steel are better,the tensile strength,yield strength,hardness,impact toughness and elongation reach 882-916 MPa,798-813 MPa,26. 2-27. 8 HRC,53-83 J and 21%-22%,respectively.