INFLUENCE OF MICROSTRUCTURE ON HIC-RESISTANCEIN H2S CONTAINING SOLUTIONS OF HIGH STRENGTH PIPELINE STEEL X65 ～ X70
显微组织对X65～X70管线钢抗H2S性能的影响

This article focused on the effect of microstructure,especially the band structure to HIC-resist-ance of pipeline in H2S containing solutions with special attentions on the initiation and expansion of cracks. OM,SEM and TEM have been used to examine the dislocation and precipitation,which have sig-nificant effect on the hydrogen induced corrosion behavior of the steels. The results indicated that the X65 with a microstmcture of homogeneous pearlite/ferrite and the XTO with homogeneous ferrite/acicular-fer-rite showed optimal resistance to HIC and the band structure should be avoided.