【摘要】 利用透射电子显微镜观察冷拔缩径变形和退火后低碳锰硼钢的组织形貌,研究了该钢的变形特征及组织演化规律.结果表明:在变形带中,铁素体沿平行于剪切应力方向形成条带状亚晶, {110}晶面为变形条带状亚晶的滑移面,条带状亚晶内存在高密度位错;经退火处理后,条带状亚晶内的位错束集成与条带状亚晶界垂直的位错胞壁,形成类方形位错胞结构;进一步经位错胞壁的扩散迁移,形成各胞壁之间呈120°夹角的亚晶结构.更多还原

【Abstract】 Microstructures of 15MnB steel after cold drawing and annealing are observed by means of transmission electron microscopy in order to investigate the evolution regularity of the deformation microstructures. The results show that the subgrain structures of the ferrite-strip along the drawing direction are formed in the deformation bands of steel. The {110} crystal planes are the slip planes of ferrite subgrain-strip, and the dense dislocations exist in the subgrains. After annealing, the denser dislocations in the strip-like subgrains are assembled into square-like cell walls which are vertical to the original subgrain-strip boundaries. The subgrain structure of 120° between the cell walls is further formed by means of the diffusion migration of dislocation cell walls.更多还原