论文标题
在裂纹尖端下氢运输的广义边界条件
Generalised boundary conditions for hydrogen transport at crack tips
论文作者
论文摘要
我们提出了一个通用框架，用于解决裂纹尖端附近的电化学扩散界面和建模氢运输。吸附和吸收动力学是通过Neumann型广义边界条件捕获的。扩散模型包括捕获的作用，具有恒定或不断发展的陷阱密度以及静水应力的影响。常规可塑性和应变梯度可塑性均用于建模固体的机械行为。与在裂纹表面处方恒定的氢浓度相比，在估计的裂纹尖端氢浓度中发现了显着差异。
We present a generalised framework for resolving the electrochemistry-diffusion interface and modelling hydrogen transport near a crack tip. The adsorption and absorption kinetics are captured by means of Neumann-type generalised boundary conditions. The diffusion model includes the role of trapping, with a constant or evolving trap density, and the influence of the hydrostatic stress. Both conventional plasticity and strain gradient plasticity are used to model the mechanical behaviour of the solid. Notable differences are found in the estimated crack tip hydrogen concentrations when comparing with the common procedure of prescribing a constant hydrogen concentration at the crack surfaces.
