标题： 准一维弹塑性模型中的疲劳裂纹扩展 显示英文标题

标题： Fatigue crack propagation in a quasi one-dimensional elasto-plastic model

摘要： 采用晶格弹簧模型，数值和解析方法均被用于研究由循环准静态载荷引起的疲劳裂纹扩展。 该系统具有准一维几何结构，由两个对称链组成，这两个链被拉开，从而断裂连接它们的弹簧，并产生裂纹扩展。 准静态裂纹扩展是由于链中弹簧内的塑性行为导致的，这意味着每个弹簧都有一个与历史相关的应力-应变曲线。 模型的连续极限允许详细的解析处理，从而深入了解扩展机制。 这个简单的模型捕捉了导致疲劳裂纹扩展已知现象的关键特征，特别是循环载荷下类似于巴黎定律的裂纹扩展规律以及过载减速效应。 显示英文摘要

摘要： Fatigue crack advance induced by the application of cyclic quasistatic loads is investigated both numerically and analytically using a lattice spring model. The system has a quasi-one-dimensional geometry, and consists in two symmetrical chains that are pulled apart, thus breaking springs which connect them, and producing the advance of a crack. Quasistatic crack advance occurs as a consequence of the plasticity included in the springs which form the chains, and that implies a history dependent stress-strain curve for each spring. The continuous limit of the model allows a detailed analytical treatment that gives physical insight of the propagation mechanism. This simple model captures key features that cause well known phenomenology in fatigue crack propagation, in particular a Paris-like law of crack advance under cyclic loading, and the overload retardation effect.