Effect of Microstructure on Deformation Behavior of Ferrite-Bainite Steels
Effect of Microstructure on Deformation Behavior of Ferrite-Bainite Steels
复制标题
显微组织对铁素体-贝氏体钢变形行为的影响
DOI：
10.2355/tetsutohagane1955.91.11_809
复制
发表时间：
2005
影响因子：
0.3
通讯作者：
Nobuo Shikanai
中科院分区：
文献类型：
--
作者：
N. Ishikawa;H. Sueyoshi;S. Endo;Nobuo Shikanai
概要：通过实验和分析研究了贝氏体体积分数对铁素体-贝氏体钢拉伸性能的影响。制备了各组成相具有相似机械性能的不同贝氏体体积分数的铁素体贝氏体钢，并研究了拉伸性能。贝氏体体积分数为16%~35%的钢具有较低的屈服比（YR）和较高的n值，而铁素体或贝氏体单相钢则表现出相对较高的YR和较低的n值。为了研究铁素体-贝氏体钢的微观变形行为，应用了基于 BCC 晶格上排列的第二相粒子规则阵列的轴对称晶胞模型。基于实际钢材，进行有限元分析，研究具有形貌特征的晶胞的宏观和微观响应。通过晶胞模型计算的铁素体-艾氏体钢的宏观变形行为与实验结果吻合良好。此外，晶胞模型很好地模拟了贝氏体体积分数对YR和n值的影响。对晶胞的显微镜观察表明，对于具有较高实验n值的铁素体16%和35%贝氏体钢，在铁素体/贝氏体边界附近的铁素体相中存在显着的应变集中。然而，贝氏体体积分数的进一步增加引起贝氏体相的塑性变形，应变集中降低，导致铁素体-58%贝氏体钢的n值水平较低。基于晶胞模型的分析研究，还讨论了贝氏体形貌对铁素体-贝氏体钢应变硬化行为的影响。
Synopsis : Effect of bainite volume fraction on tensile properties of ferrite-bainite steels was investigated experimentally and analytically . Ferritebainite steels with different bainite volume fractions having the similar mechanical properties for each constituent phase were prepared and the tensile properties were investigated. Lower yield ratio (YR) and higher n-value were obtained for the steels with bainite volume fraction of 16 to 35%, while the ferrite or bainite single phase steels exhibited relatively higher YR and lower n-value. In order to investigate microscopic deformation behavior of ferrite-bainite steels, an axisymmetric unit cell model based on a regular array of second-phase particles arranged on a BCC lattice was applied. Finite element analyses were carried out to investigate the macroscopic and microscopic response of unit cells with morphological features based on the actual steels. Macroscopic deformation behavior of ferrite-ainite steels calculated by the unit cell model showed good agreement with experimental results. In addition, the effect of bainite volume fraction on YR and n-value was well simulated by the unit cell model. Microscopic investigation on the unit cells revealed that significant strain concentration existed in the ferrite phase near the ferrite/bainite boundary for ferrite-16% and 35% bainite steel, which had higher experimental n-value . However, further increasing of bainite volume fraction caused plastic deformation of bainite phase and the strain concentration was decreased , resulting in lower level of n-value for ferrite-58% bainite steel. Effect of bainite morphology on strain hardening behavior of ferrite-bainite steels was also discussed based on analytical study using the unit cell model .