Hydrogen is well known to embrittle high-strength steels and impair their corrosion resistance. One of the most attractive methods to mitigate hydrogen embrittlement employs nanoprecipitates, which are widely used for strengthening, to trap and diffuse hydrogen from enriching at vulnerable locations within the materials. However, the atomic origin of hydrogen-trapping remains elusive, especially in incoherent nanoprecipitates. Here, by combining in-situ scanning Kelvin probe force microscopy and aberration-corrected transmission electron microscopy, we unveil distinct scenarios of hydrogen-precipitate interaction in a high-strength low-alloyed martensitic steel. It is found that not all incoherent interfaces are trapping hydrogen; some may even exclude hydrogen. Atomic-scale structural and chemical features of the very interfaces suggest that carbon/sulfur vacancies on the precipitate surface and tensile strain fields in the nearby matrix likely determine the hydrogen-trapping characteristics of the interface. These findings provide fundamental insights that may lead to a better coupling of precipitation-strengthening strategy with hydrogen-insensitive designs.

众所周知，氢会使高强度钢变脆并削弱其耐腐蚀性。减轻氢脆的最有吸引力的方法之一是使用广泛用于强化的纳米沉淀物，以捕获和扩散氢在材料内的脆弱位置富集。然而，氢捕获的原子起源仍然难以捉摸，尤其是在不相干的纳米沉淀物中。在这里，通过结合原位扫描开尔文探针力显微镜和像差校正透射电子显微镜，我们揭示了高强度低合金马氏体钢中氢-沉淀物相互作用的不同场景。发现并非所有非相干界面都捕获氢；有些甚至可能排除氢。界面的原子级结构和化学特征表明，沉淀物表面的碳/硫空位和附近基质中的拉伸应变场可能决定了界面的氢捕获特性。这些发现提供了基本的见解，可能会导致沉淀强化策略与氢不敏感设计更好地结合。