摘要
在室温下对退火Fe-24Mn-1Si-1.5Al-0.045CTWIP钢进行了不同程度的拉伸变形,采用JEM-2100透射电子显微镜对变形后的组织形貌进行表征和分析。研究结果表明:在变形初期,晶粒内存在着大量位错,它们相互缠结,呈胞状结构。在此阶段,位错滑移为主要变形机制。随着变形量的增加,形变孪晶在晶界等处形成,孪生机制被激活,孪生和滑移机制相互竞争。双孪生系统在大多数晶粒内先后被激活,孪生和滑移机制相互交割,起到动态细化晶粒的作用,使强度显著提高。在变形后期,试验钢的变形机制主要是TRIP效应,以及孪生与滑移的相互作用而诱发了去孪生机制,层状组织出现,孪晶特征减弱,从而导致样品的局部变形和失效。
The microstructures of an annealed TWIP steel （Fe-24Mn-1Si-1.5Al-0. 045C） with tensile deformation of different degrees at room temperature were systematically investigated with JEM-2100 transmission electron microscope. The results show that in early deformation stage, a large number of dislocations with a cellular struc- ture tangle each other in grains. At this stage, dislocation slip is the main deformation mechanism. With increasing amount of deformation, deformation twins form at grain boundaries, twinning mechanism is activated, and mech- anisms of twinning and slip compete with each other. Double twin systems are activated in most of grains, twins cross through each other, which plays a role of dynamic grain refinement and makes the strength increase signifi- cantly. In later stage of deformation, TRIP effect is main deformation mechanism, interaction between twinning and slip induces de-twinning mechanism, layered structure appears, and twinning feature weakens, resulting in the local deformation and failure of sample.
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2015年第1期61-66,共6页
Journal of Iron and Steel Research
