Prediction of hydrogen embrittlement requires a robust modelling approach and this will foster the safe adoption of hydrogen as a clean energy vector. A generalised computational model for hydrogen embrittlement is here presented, based on a phase field description of fracture. In combination with Part I of this work, which describes the process of hydrogen uptake and transport, this allows simulating a wide range of hydrogen transport and embrittlement phenomena. The material toughness is defined as a function of the hydrogen content and both elastic and elastic-plastic material behaviour are incorporated, enabling to capture both ductile and brittle fractures, and the transition from one to the other. The accumulation of hydrogen near a crack tip and subsequent embrittlement is numerically evaluated in a single-edge cracked plate, a boundary layer model and a 3D vessel case study, demonstrating the potential of the framework. Emphasis is placed on the numerical implementation, which is carried out in the finite element package COMSOL Multiphysics, and the models are made freely available.

翻译：氢脆预测需要稳健的建模方法，这将促进氢作为清洁能源载体的安全应用。本文提出了一种基于相场断裂描述的氢脆通用计算模型。结合本工作第一部分（描述了氢吸收与传输过程），该模型能够模拟广泛的氢传输与脆化现象。材料韧性被定义为氢含量的函数，同时纳入了弹性和弹塑性材料行为，从而能够捕捉韧性断裂、脆性断裂以及两者之间的转变。通过单边裂纹板、边界层模型和三维容器案例研究，对裂纹尖端附近氢的积累及后续脆化进行了数值评估，展示了该框架的潜力。重点阐述了在有限元软件包COMSOL Multiphysics中实现的数值方法，相关模型已开源提供。