一种新型的低周疲劳裂纹扩展速率模型  

A new model of low cycle fatigue crack growth rate

作　　者：吴晓松[1] 陈荐[1] 何建军[1] 任延杰[1] 高鹏[1] 

机构地区：[1]长沙理工大学能源高效清洁利用湖南省普通高等学校重点实验室,湖南长沙410004

出　　处：《长沙理工大学学报（自然科学版）》2011年第1期56-60,共5页Journal of Changsha University of Science and Technology:Natural Science

基　　金：国家自然科学基金资助项目(50775015)

摘　　要：基于低周疲劳裂纹扩展机制,假设裂纹尖端循环塑性区内应变分布服从HRR理论解,利用裂纹尖端锐化、钝化启裂低周疲劳裂纹扩展机制,结合Ramberg-Osgood循环应力应变曲线和Manson-Coffin疲劳寿命曲线等断裂力学理论,推导出一种新的低周疲劳裂纹扩展速率数学模型.与30Cr1Mo1V和St-4340的低周疲劳裂纹扩展速率试验数据进行对比,结果表明该低周疲劳裂纹扩展速率模型能够较好地预测材料的低周疲劳裂纹扩展速率.The plastic strain at crack tip of low cycle fatigue and the strain distribution on the cyclic plasticity zone of crack tip obey the HRR theoretical solution approximately were analyzed in this paper.A new low cycle fatigue crack growth mathematical model is derived by the combination of these mechanisms which include the crack tip sharpen,the passivation rev crack and crack interaction mechanics and the Ramberg-Osgood＇s circulation stress-strain curve and the Coffin-Manson＇s fatigue life curve.The experimental data of low cycle fatigue crack growth rate which belongs to the 30Cr1Mo1V and St-4340 are contrasted.The comparison result shows that the low cycle fatigue crack growth rate model adopted in this paper is able to predict reasonably the low cycle fatigue crack growth rate of the materials used.

关 键 词：低周疲劳 裂纹扩展 模型 塑性应变 

分 类 号：TB301[一般工业技术—材料科学与工程]