论文部分内容阅读
在500℃采用C方式ECAP变形制备了亚微晶45钢,用光学显微镜(OM)、透射电子显微镜(TEM)和电子衍射(SAED)等分析技术对其进行表征,研究了铁素体组织的演变特征和晶粒细化机制。结果表明:在初始变形道次后,原始的粗大铁素体晶粒因剧烈剪切变形而沿着剪切变形的方向形成剪切变形带,在其内大量的具有亚微米尺寸的板条状位错胞或亚晶使铁素体晶粒显著细化。进一步变形使板条状位错胞或亚晶组织继续细化,但不明显。随着ECAP变形道次的增加,以晶界滑移和晶粒转动的方式最终获得等轴状且具有大角度晶界分离的亚微晶组织。
The submicron 45 steel was prepared by ECAP with C mode at 500 ℃. The microstructure of 45 steel was characterized by optical microscope (OM), transmission electron microscopy (TEM) and electron diffraction (SAED). The effects of ferrite microstructure Evolution characteristics and grain refinement mechanism. The results show that after the initial deformation pass, the original coarse ferrite grains form shear deformation zone along the direction of shear deformation due to the intense shear deformation, in which a large number of slab-shaped with submicron size Dislocation cells or subgrains significantly refine ferrite grains. Further deformation of lamellar dislocation cells or subgrain organization continue to refine, but not obvious. With the increase of ECAP deformation pass, the submicrocrystalline microstructure with equiaxed and high-angle grain boundary separation was finally obtained by means of grain boundary slip and grain rotation.