Abstract Mechanical properties of metals can deteriorate under the influence of hydrogen. This effect on the fatigue behavior of steels is a matter of particular interest for industrial applications regarding environmentally friendly energy solutions. A framework for the computational modeling of fatigue life is proposed considering the hydrogen diffusion within the metal microstructures. Furthermore, the mutual influence of the microstructure, hydrogen transport and the elasto-plastic material response are taken into account by means of a coupled crystal plasticity-diffusion finite element model. All steps necessary for an estimation of the fatigue lifetime, including the microstructure characterization, the determination of cyclic material parameters, the deformation-diffusion simulation and the evaluation of fatigue indicator parameters to predict the number of cycles to fatigue crack initiation, are described in this work. Validation of the presented model is carried out on the ferritic steel 1.4003. Numerical results are compared to experimental data and reveal the suitability of the proposed method for crack initiation lifetime prediction of parts getting in contact with hydrogen.

中文翻译：

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氢气氛下疲劳裂纹萌生的微观力学模型

摘要 金属的机械性能会在氢的影响下恶化。这种对钢疲劳行为的影响是有关环保能源解决方案的工业应用的一个特别关注的问题。考虑到金属微结构内的氢扩散，提出了疲劳寿命计算模型的框架。此外，通过耦合晶体塑性扩散有限元模型考虑了微观结构、氢传输和弹塑性材料响应的相互影响。估计疲劳寿命所需的所有步骤，包括微观结构表征、循环材料参数的确定、在这项工作中描述了变形扩散模拟和疲劳指标参数的评估，以预测疲劳裂纹萌生的循环次数。所提出模型的验证是在铁素体钢 1.4003 上进行的。数值结果与实验数据进行了比较，揭示了所提出的方法对与氢接触的零件的裂纹萌生寿命预测的适用性。