A two-stage micromechanics model for short fatigue cracks
A two-stage micromechanics model for short fatigue cracks
复制标题
短疲劳裂纹的两阶段微观力学模型
DOI：
10.1016/0013-7944(93)90034-p
复制
发表时间：
1993
影响因子：
5.4
通讯作者：
A. Navarro
中科院分区：
文献类型：
--
作者：
K. Hussain;E. R. Rios;A. Navarro
在模拟热影响区（HAZ）组织中研究了组织对C-Mn钢表面短裂纹扩展行为的影响。通过在扭转和推拉载荷下复制沙漏试样来进行裂纹萌生检测和裂纹扩展测量。原奥氏体晶界铁素体的长度被表征为有效的微观结构参数。扩展速率受微观结构的影响;当裂纹接近晶界时，扩展速率降低，当裂纹穿过晶界时，扩展速率再次增加。短裂纹扩展模型提出的其他研究人员进行了严格审查，并提出了一个修改后的模型，基于微观力学的裂纹扩展速率的微观结构的影响。模型预测的裂纹扩展行为与实验结果吻合较好。
The influence of microstructure on the propagation behavior of short surface cracks is examined in a simulated HAZ microstructure in C Mn steel. The detection of crack initiation and crack growth measurement is carried out by the replication of hourglass specimens under torsional and push-pull loading. The length of ferrite at the prior austenite grain boundaries is characterized as the effective microstructural parameter. Propagation rate is affected by the microstructure; it decreases when the crack approaches the grain boundary and increases again when it crosses the grain boundary. The short crack growth models proposed by other researchers are critically examined and a modified model based on micromechanics is presented to incorporate the effect of microstructure on the rate of crack growth. The crack growth behavior predicted by the model matches closely with the experimental results.