Biomimetic corrosion resistant aluminium for aeronautics
“Drop climbing, Amai. Noi ci muoviamo così, scaliamo la pioggia. Presto, forse, imparerà anche lei”
From: Storia interiore dell’universo, P. Vismara
The research activity, co-funded by the European Union– Next Generation EU, PNRR ‐ missione 4 “istruzione e ricerca” ‐ componente C2 investimento 1.1 “fondo per il programma nazionale di ricerca e progetti di rilevante interesse nazionale (PRIN)” D.D. N. 104/2022 “BANDO PRIN 2022”, aims to functionalize the surface of aluminum alloy 2024, among the most used in the aeronautical sector, in order to reduce surface fluid dynamic turbulence in contact with fluids (air, water) and to improve corrosion resistance in aggressive environments.
The objective of the research is twofold:
1. To mimic on the metal surface a texture inspired by the microscopic structure of the skin of the “mako” shark, characterized by the presence of grooves (the so-called “riblets”) capable of reducing fluid-dynamic friction, improving performance,
2. To improve the corrosion resistance of components made of AA 2024 through plasma anodic oxidation (PEO, Plasma Electrolytic Oxidation) treatments.
The project, coordinated by prof. Andrea Brenna as Principal Investigator, is carried out in collaboration with the University of Trento (unit manager: prof. Michele Fedel).
The work team of the Politecnico di Milano research unit is completed by prof. Marco Ormellese and Dr. Matteo Gamba, both members of PoliLaPP research group.
The work team of the University of Trento research unit is completed by Dr. Andrea Cristoforetti.
The research activity lasts two years and is divided into different phases:
- Selection of the surface and bio-mimetic texture to be reproduced on aluminium 2024, determining the shape and size of the “riblets” using fluid dynamic calculation approaches
- Creation of the texture on the metal, choosing the proper electrochemical and/or micro-machining technique
- Optimization of the PEO anodizing process on aluminum alloy 2024, in order to obtain a robust, thick and protective surface oxide
- Application of PEO to the aluminum substrate texturized with the mako “riblets”
- Verification of the corrosion behavior of the material through accelerated tests and long-term exposure tests.
Visit the LinkedIn page of the “MAKO” Project to stay updated on the progress of the research