Metallipinnat

Metallipinnat is a term used in materials science to describe metallic surfaces engineered with pronounced micro- and nano-scale protrusions that resemble pinnate structures. The resulting textures increase surface roughness and can influence optical, catalytic, and mechanical properties of the metal.

The term is derived from the Finnish words metall i meaning metal and pinnat meaning surfaces or facets; in Nordic technical literature it is used to describe a class of engineered metal surfaces characterized by high aspect ratio features such as ridges, needles, or island-like protrusions arranged in irregular patterns.

Fabrication methods include electrochemical etching and anodization to create porous and coral-like morphologies, laser texturing, lithography-based patterning, and templated or deposition-based approaches that induce controlled roughness on metals such as nickel, copper, aluminum, and titanium.

Key properties include increased surface area, altered reflectivity, enhanced catalytic activity, and modified wetting behavior. The roughened morphology can improve heat transfer in fins, light absorption in photovoltaic and sensing devices, and efficiency of photocatalytic reactions by providing active sites.

Challenges include mechanical stability of fine features under wear, contamination of pores, and reproducibility across large areas. Ongoing research studies the relationship between feature geometry, material choice, and performance in real-world environments.

See also: nanostructured metal surfaces, textured metal surfaces.