论文标题
相场断裂在建模氢辅助故障中的应用
Applications of phase field fracture in modelling hydrogen assisted failures
论文作者
论文摘要
相位场断裂方法已成为一种有前途的计算工具,用于建模各种问题,包括最近的氢化和应力腐蚀破裂。在这项工作中,我们证明了基于相位的多物理模型在转换含氢气环境中结构成分的工程评估和设计方面的潜力。首先,我们提出一个理论和数值框架耦合变形,扩散和断裂,该耦合构成惯性效应。裂纹密度函数的几个本构构选择被考虑,包括在损伤响应中具有和没有弹性阶段的选择。材料韧性定义为使用原子化的氢降解定律的氢含量的函数。该模型使用有限元方法在2D和3D中实现。由此产生的计算框架用于解决特定工程兴趣的许多案例研究。这些旨在在以下方式中展示模型功能:(i)捕获复杂的断裂现象,例如动态裂纹分支或无效裂缝相互作用,(ii)通过构图通过COUTITION PRODECORTIONS模拟基于模拟的螺栓,(III)启用基于虚拟测试或数字型Twins的模拟模型,对关键组件进行模拟标准化测试,以及(III)启用基于模拟的范式,以实现模拟范围。可以预测在服务条件下缺陷的演变,直到最终失败。通过重现缺陷的精确几何形状,而不是重新表征它们作为锋利的裂纹,相场建模可以使更现实有效的结构完整性评估。
The phase field fracture method has emerged as a promising computational tool for modelling a variety of problems including, since recently, hydrogen embrittlement and stress corrosion cracking. In this work, we demonstrate the potential of phase field-based multi-physics models in transforming the engineering assessment and design of structural components in hydrogen-containing environments. First, we present a theoretical and numerical framework coupling deformation, diffusion and fracture, which accounts for inertia effects.Several constitutive choices are considered for the crack density function, including choices with and without an elastic phase in the damage response. The material toughness is defined as a function of the hydrogen content using an atomistically-informed hydrogen degradation law. The model is numerically implemented in 2D and 3D using the finite element method. The resulting computational framework is used to address a number of case studies of particular engineering interest. These are intended to showcase the model capabilities in: (i) capturing complex fracture phenomena, such as dynamic crack branching or void-crack interactions, (ii) simulating standardised tests for critical components, such as bolts, and (iii) enabling simulation-based paradigms such as Virtual Testing or Digital Twins by coupling model predictions with inspection data of large-scale engineering components. The evolution of defects under in-service conditions can be predicted, up to the ultimate failure. By reproducing the precise geometry of the defects, as opposed to re-characterising them as sharp cracks, phase field modelling enables more realistic and effective structural integrity assessments.