Dette, UlrikeUlrikeDetteSchaan, GunnarGunnarSchaanShi, ShanShanShi2026-10-072026-10-072026-09-22Materials and Design 271: 117082 (2026)https://hdl.handle.net/11420/65203As the demand for light-weight structural and functional materials grows, the fabrication of hierarchical, high-performance micro- and nano-architectures becomes increasingly important. Here, we present a scalable alloying–dealloying strategy to fabricate porous metal with two- and three-level hierarchical networks (2 L-/3L-HN). By exploiting the vapour pressure difference between Ni and Zn, vapour phase alloying of Ni foam with Zn, followed by vapour phase dealloying of the resulting γ-Zn84Ni16 foam, generates a second hierarchical level, producing 2L-HN Ni or 2L-HN β-Zn50Ni50. Re-alloying 2L-HN β-Zn50Ni50 to 2L-HN γ-Zn84Ni16 via vapour phase alloying while preserving its hierarchical architecture enables chemical dealloying to create a third level of hierarchy at the nanoscale, producing 3L-HN Ni with significantly increased specific surface area. A novel scaling law is proposed to predict the mechanical properties of these hierarchical porous metallic networks as a function of solid fraction, and its validity is supported by compression tests on 2L-HN Ni with varying densities. This work establishes a scalable and versatile route for fabricating multiscale porous metallic networks with light-weight, tunable mechanical performance and high surface area.en1873-41972026Elsevierhttps://creativecommons.org/licenses/by/4.0/Hierarchical nanoporous NiMechanical propertiesMetal foamsVapour phase alloyingVapour phase dealloyingTechnology::620: Engineering::620.1: Engineering Mechanics and Materials ScienceJournal Article10.1016/j.matdes.2026.11708210.15480/882.18770