A review of a time-dependent fracture life law (or model) based on a proposed multi-scale analysis
A review of a time-dependent fracture life law (or model) based on a proposed multi-scale analysis
复制标题
基于所提出的多尺度分析对随时间变化的断裂寿命定律（或模型）进行回顾
DOI：
10.3233/sfc-150170
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
R. Ainsworth
中科院分区：
文献类型：
--
作者：
A. Yokobori;R. Sugiura;T. Ohmi;R. Ainsworth
为了解决时变断裂条件下的结构安全问题，提出了一种从纳米尺度到宏观尺度的多尺度混合力学算法。本文提出了一种将材料物理与蠕变裂纹扩展确定的寿命预测联系起来的算法，并解决了实际应用问题，使“断裂预测”能够在该算法的基础上从“阐明断裂机制的科学”发展成为“断裂预测”。特别是，为了预测实际部件的断裂寿命，由空位扩散引起的空隙力学（微观机械因素）、应力三轴性、TF（结构力学因素）和材料结构（细观机械因素）之间的联系的重要性在所提出的蠕变裂纹扩展热激活过程的激活能公式中得到体现。对这些问题以及基于多尺度分析建立蠕变裂纹扩展寿命规律的相关算法进行了详细讨论，范围从微观损伤到结构脆性。
To solve the problem of structural safety under time-dependent fracture conditions, an algorithm of multi-scale hy- brid mechanics from the nano-scale to the macro-scales is described. The paper presents an algorithm that links the physics of materials with life prediction determined by creep crack growth and addresses practical application which enables "predic- tion of fracture" to be developed from "the science of clarification of fracture mechanism" on the basis of the algorithm. In particular, in order to predict the fracture life of real components, the importance of the link between void mechanics caused by vacancy diffusion (micro mechanical factor), the stress tri-axiality, TF (a structural mechanical factor), and the material structure (a meso-mechanical factor) is shown in the proposed formulation for the activation energy of the thermally activated process of creep crack growth. A detailed discussion on these issues as well as on the algorithm relevant to the establishment of the law of creep crack growth life based on the multi-scale analysis is included ranging from the scale of micro damage to structural brittleness.