【摘要】 利用扫描电镜(SEM)和透射电镜(TEM)对不同工艺轧制的X80管线钢的显微组织和位错形态进行了观察和分析。利用电子背散射衍射(EBSD)技术分析了X80管线钢的有效晶粒尺寸。比较和分析了4种控轧控冷工艺对钢板的组织和力学性能的影响。研究得出,采用奥氏体再结晶区控温轧制+未再结晶区近两相区轧制+轧后直接水冷工艺,得到的钢板的有效晶粒尺寸最小、力学性能最佳,其组织以粒状贝氏体为主,并伴有板条贝氏体铁素体、针状铁素体、准多边形铁素体以及少量M/A多相共存的复合组织,使试验钢获得了良好的强韧性匹配。更多还原

【Abstract】 The microstructure and dislocation of X80 pipeline steel produced with different rolling processes were observed and analyzed by means of scanning electron microscope( SEM) and transmission electron microscope( TEM). And effective grain size of X80 pipeline steel was analyzed by electron backscatter diffraction( EBSD) technique. The influences of four controlled rolling and controlled cooling processes on microstructure and mechanical properties of steel plate were compared and analyzed. The results showed that the steel plate produced by the process sequence of temperature-controlled rolling in austenite recrystallization zone plus nearly two-phase region rolling in unrecrystallization zone plus direct water cooling after rolling,offered the best mechanical properties,the smallest effective grain size,and the microstructure was mainly granular bainite,accompanied by lath bainite ferrite,acicular ferrite,quasi-polygonal ferrite and a small amount of M/A,exhibiting good combination of strength and toughness.更多还原