摘要
利用常规力学性能测试设备和透射电镜研究了不同回火温度对一种高强度X120管线钢的显微组织与力学性能的影响。结果表明,试验钢经回火处理后板条间M/A膜明显弱化,贝氏体板条出现粗化和合并,板条间界呈锯齿状发展,原有析出相长大并有含Nb第二相进一步析出;随着回火温度的升高,试验钢中的贝氏体板条宽度增大,小角度晶界所占比例增加。热轧态试验钢的力学性能优良:R eL=920 MPa,R m=1100 MPa,A=13.0%,KV2(-20℃)=227 J;但是随着回火温度从450℃升高到610℃,材料的屈服强度从910 MPa增大至970 MPa;冲击吸收能量(-20℃)从213 J降至173 J;抗拉强度在1010 MPa和982 MPa之间波动,530℃回火时最小。
Effects of different tempering temperatures on microstructure and mechanical properties of high strength X 120 pipeline steel were studied by the mechanical properties testing equipment and transmission electron microscope .The results show that the M/A membrane between the laths in the tested steel after tempered weakens significantly , the bainite laths become coarse and merge gradually , grain boundaries between laths become serrated , original precipitates grow and some phase containing Nb precipitate in the tempered steel .With increasing of the tempering temperature , the width of the single bainite-lath and the proportion of small angle grain boundary are increased . The ReL, Rm, A and KV2 （ -20 ℃） of the hot rolled steel reach to 920 MPa, 1100 MPa, 13.0% and 227 J, respectively.But with increasing of the tempering temperature from 450℃to 610℃, the yield strength is increased from 910 MPa to 970 MPa, whereas the impact absorbed energy （-20 ℃） decreases from 213 J to 173 J.The tensile strength is raries from 1010MPa to 982 MPa,and the minimal value for the steel is tempered at 530 ℃.
出处
《金属热处理》
CAS
CSCD
北大核心
2013年第10期5-10,共6页
Heat Treatment of Metals
关键词
X120管线钢
回火温度
微观结构
力学性能
X120 pipeline steel
tempering temperature
microstructure
mechanical property
