A fabrication method for vertical oxide nano-rod array by internal oxidation of alloys at high-temperatures

A simple metallurgical process for fabricating vertical oxide nano-rod array structures with internal oxidation of alloys is described. Oxidation at high-temperatures and under low oxygen partial pressures can develop internally rod-like oxide precipitates in some dilute alloys such as Ni(Al) solid solutions. The vertical oxide nano-rod arrays can be developed on the metal substrates or components by removing the metallic matrix of the internal oxidation zone. Al2O3 or NiAl2O4 spinel nano-rod arrays were prepared by using M(Al) solid solutions. Pack cementation process to develop Ni(Al) solid solution zone on a metal surface was used for the fabrication of vertical nano-rod arrays on Ni substrates with desired shape. Near-net shape Ni substrates with vertical oxide nano-rod array structures on their surfaces can be prepared by using pack cementation and internal oxidation. Fabrication of vertical nano-rod arrays with Co(Al) and Fe(Al) solid solutions were also described briefly.