Metal Nanocomposites\nReinforced by Ceramic Nanoarchitecture:\nExploiting Extrinsic Size Effects for High Mechanical Strength

The pursuit of harnessing superior mechanical properties\nachieved\nthrough the size effect on a macroscopic scale has been a prominent\nfocus in engineering, as size-induced strengthening is enabled only\nin the nanoscale regime. This study presents a metal/ceramic/metal\n(MCM) nanocomposite reinforced by ceramic nanoarchitectures. Through\nproximity-field nanopatterning, the inch-scale production of nanoarchitecture\nfilms is enabled in a single fabrication step. The developed three-dimensional\n(3D) Ni/Al<sub>2</sub>O<sub>3</sub>/Ni nanocomposite film exhibits\nsignificantly high compressive strength, corresponding to an increase\nof approximately 30% compared with that calculated using the upper\nlimits of the conventional rule of mixtures. The exceptional strength\nof the 3D MCM nanocomposite can be attributed to the extrinsic size\neffect of the ceramic nanoarchitectures. By combining size-induced\nstrengthening of ceramics with the strengthening law for composites,\na new type of strengthening model is derived and experimentally validated\nusing the 3D MCM nanocomposite.