金属材料疲劳裂纹扩展机制及模型的研究进展

Recent Research Progress on Mechanisms and Models of Fatigue Crack Growth for Metallic Materials

裂纹的萌生、扩展和断裂行为及其与材料本身和外部因素的关联一直是工程与科学领域的重要研究课题.论文总结了影响金属材料疲劳裂纹扩展的多种因素,综述了高周疲劳裂纹扩展的唯象模型和理论模型,以及低周和超高周疲劳裂纹扩展模型的最新进展(包括基于能量的和考虑概率的).综合前述模型优缺点,提出了一种基于单轴拉伸性能的新型疲劳裂纹扩展模型(iLAPS).分析表明,新模型iLAPS与多种常用材料的疲劳裂纹扩展试验数据吻合较好,并且能够准确地给出不同应力比下的裂纹扩展速率曲线.最后,对先进材料抗疲劳开裂性能的高通量表征及运维技术进行了展望.

As a significant research subject in engineering science,the relation of the fatigue performance with the material and environment has gained increasing attention in both academic and industrial communities.Current paper reviews the main affecting factors of crack growth as well as the phenomenological or theoretical models in the high cycle fatigue regime.Meanwhile,the approaches to estimate the crack growth rate in the low-and very-high-cycle fatigue regimes are given in detail by taking into account the energy principle and probabilistic dispersion.After defining the disadvantages of provided methods,a new model,called iLAPS,is proposed based on uniaxial tensile behavior.It is found that the predictions from the newly-developed model are in good agreement with the experimental results under various stress ratios.Finally,the high-thoughput characterization and management technology are expected to be adopted to predict and evaluate the fatigue resistance of advanced materials.