Prediction of Low Cycle Fatigue Crack Growth under Mixed-mode Loading Conditions Using Cohesive Zone Models☆
Prediction of Low Cycle Fatigue Crack Growth under Mixed-mode Loading Conditions Using Cohesive Zone Models☆
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使用内聚区模型预测混合模式加载条件下的低周疲劳裂纹扩展â
DOI：
10.1016/j.proeng.2014.12.665
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Xiao Li
中科院分区：
文献类型：
--
作者：
Huang Yuan;Huan Li;Xiao Li
对于高周和低周疲劳问题，损伤容限设计都基于可靠的疲劳裂纹扩展方法。虽然准弹性材料中的裂纹扩展寿命可以应用巴黎定律来估算，但弹塑性疲劳裂纹扩展需要更精确的计算模型。在过去的十年中，人们提出并研究了许多用于预测弹塑性疲劳裂纹扩展的粘聚区模型。然而，大多数粘聚区模型被用来再现疲劳裂纹扩展的小范围屈服，并且不能用有限塑性区来预测低周疲劳裂纹扩展。本文针对高疲劳裂纹扩展速率提出了一种新的CCZM模型，并试图对延性材料中从循环疲劳裂纹扩展到弹塑性断裂的过程给出统一的描述。内聚力模型中的损伤累积方程既包含单调损伤，又包含循环损伤机制。通过紧凑型拉伸(CT)试件和紧凑型拉伸剪切(CTS)试件在复合加载条件下的断裂试验和疲劳裂纹扩展试验，对AISI 304奥氏体不锈钢进行了试验验证。详细的有限元计算结果表明，本文提出的粘聚区模型能够统一描述疲劳裂纹的整个扩展过程。模型参数可以在常规CT试件中确定。粘聚区模型有可能应用于更复杂的结构破坏分析。
Damage tolerant design is based on reliable fatigue crack growth methods for both high cycle and low cycle fatigue problems. While the Paris’ law can be applied for estimate crack growth life in quasi-elastic materials, elastic-plastic fatigue crack growth needs more accurate computational models. In the past decade numerous cohesive zone models were proposed and investigated for predicting elastic-plastic fatigue crack growth. However, most cohesive zone models were used to reproduce fatigue crack growth with vanishingly small scale yielding and failed to predict low cycle fatigue crack growth with the finite plastic zone. In the present work a new CCZM is introduced for the high fatigue crack growth rate and attempting to give a uniform description from cyclic fatigue crack growth to elastoplastic rupture in ductile materials. The damage accumulation equation in the cohesive model contains both monotonic damage as well as cyclic damage mechanism. Experimental verification was carried out in an austenitic stainless steel AISI 304 through fracture tests and fatigue crack growth tests of compact tension (CT) specimens under mode I and compact-tension shear (CTS) specimens under mixed mode loading conditions. Detailed finite element computations confirmed that the present cohesive zone model provides a uniform description for the whole fatigue crack growth regimes. The model parameters can be determined in the conventional CT specimens. The cohesive zone model has the potential to be applied for more complex structural failure analysis.
影响因子：
3.7
作者：
H. Li;Huang Yuan
通讯作者：
H. Li;Huang Yuan