摘要
为了提高石油输送管线钢的等级及韧性,对超低碳微合金钢通过控制轧制后的三阶段冷却,在实验室试制了X100高钢级管线钢,并对其显微组织与力学性能进行了分析。结果表明:试验钢在拉伸过程中没有明显的屈服点,屈服强度达770 MPa,屈强比为0.80,伸长率达到21.3%,-20℃冲击功为179 J,均符合标准要求,具有良好的综合力学性能;试验钢在冷却过程中发生了位错回复、亚晶形成、形变诱导析出、针状铁素体以及板条贝氏体的转变、析出物长大和碳化物偏聚等,形成了针状铁素体和贝氏体双相组织为主及部分M-A岛和孪晶的显微组织。
In order to improve the grade and ductility of pipeline steel in petroleum transportation,high grade pipeline steel X100 was trial-produced in lab using ultralow-carbon microalloy by cooling with three stages after controlled rolling.The microstructure and mechanical properties of the steel were analyzed.The results show that during tensile test the steel had high comprehensive mechanical properties as follows：the yield point was unconspicuous,yield strength was up to 770 MPa,yield-to-strength ratio was 0.80,elongation was up to 21.3% and impact energy at -20℃was 179 J.All the properties could meet standard requirements.Dislocation recovery, sub-grain formation,deformation-induced precipitation,acicular ferrite and lath bainite transformation,precipitation growth and carbide accumulation occurred in the steel during the cooling process.The microstructure was dualphase of acicular ferrite and lath bainite with a small amount of M-A islands and twins.
出处
《机械工程材料》
CAS
CSCD
北大核心
2010年第4期47-50,54,共5页
Materials For Mechanical Engineering
