Hydrogen embrittlement (HE) of advanced high-strength steels is a crucial problem in the automotive industry, which may cause time-delayed failure of car body components. Practical approaches for evaluating the HE risk are often partially and contradictive in nature, because of hydrogen desorption during testing and inhomogenous hydrogen distributions in, e.g., notched samples. Therefore, the present work aims to provide fully parametrized and validated bulk diffusion models for three dual phase steels to simulate long-range chemical diffusion, trapping and hydrogen desorption from the surface. With one constant set of parameters, the models are able to predict the temperature dependency of measured Choo-Lee plots as well as the concentration dependency of measured effective diffusion coefficients. Finally, the parametrized and validated bulk diffusion models are applied for studying the role of the current density on the permeation time and the role of coatings as effective diffusion barriers.
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机译:先进高强度钢的氢脆(HE)是汽车工业中的关键问题,可能导致车身部件的延时失效。评估 HE 风险的实用方法在本质上通常是部分的和矛盾的,因为在测试过程中氢气解吸和氢气分布不均匀,例如缺口样品。因此,本工作旨在为三种双相钢提供完全参数化和验证的体扩散模型,以模拟表面的长程化学扩散、捕获和氢气解吸。使用一组恒定参数,这些模型能够预测测得的Choo-Lee图的温度依赖性以及测量的有效扩散系数的浓度依赖性。最后,应用参数化和验证的体扩散模型研究了电流密度对渗透时间的作用以及涂层作为有效扩散屏障的作用。
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