X65MO海底管线钢包辛格效应研究

海底管线钢管强度是包辛格效应和形变强度共同作用的结果。采用MTS材料试验机、扫描电镜和透射电镜，研究了不同预压变形量下X65MO海底管线钢的包辛格效应。研究结果表明，预压变形量在0~0.85%时，包辛格效应占据主导作用，X65MO钢管的屈服强度较原料带钢的低，当预压变形量约为0.30%时，屈服强度下降值达到最大约30 MPa；预压变形量在085%~1.50%时，形变强化效应占主导作用，X65MO钢管的屈服强度较原料带钢的高。随着预压变形量的增加，X65MO钢晶粒内部形成的稳定位错亚结构增多，并且第二相粒子对位错钉扎作用更加显著，导致了宏观上钢管屈服强度的增加。

Research on Bauschinger effect of X65MO submarine pipeline steel

The strength of submarine pipeline pipe is the result of the combined effect of Bauschinger effect and deformation strength.Using the MTS material testing machine,scanning electron microscope and transmission electron microscope,the Bausinger effects of X65MO submarine pipeline steel under different pre compression deformation rates were studied.The results show that the Bausinger effect dominates when the pre-compression deformation rate is 0-0.85%.The yield strength of X65MO pipe is lower than that of the raw strip.When the pre-compression deformation rate is 0.30%,the maximum decreased values of yield strength is 30 MPa.When the pre-compression deformation is 0.85%-1.50%,the deformation strengthening effect dominates,and the yield strength of X65MO steel pipe is higher than that of the raw strip.As the amount of pre-compression deformation increases,the stable dislocation substructure formed inside the X65MO steel grains is increases,and the effect of the second phase particles on the dislocation pinning is more significant,which resulting in an increase in yield strength of the pipe.