Maybe the Work of Professor Aizenberg could be interesting for your work (https://aizenberglab.seas.harvard.edu/papers/2013%20Nano%20Lett%20Hierarchical%20or%20Not-Boehmite%20SLIPS.pdf)
PTFE (Poly tetra fluoro ethylene) polymer type materials have extremely low coefficient of friction and are "non-sticking" to most materials. So, will be useful for Al and Al alloys substrate. You can proceed your projects with this kind of polymer material