Evaluation of the effectiveness and durability of commercial non-stick coatings

In this study, four commercial non-stick coatings (two fluoropolymer and two ceramic) were characterized by micrography, Raman spectroscopy and energy dispersive X-ray spectroscopy (EDX). A pancake batter was then baked on coated aluminum substrates. In a first test, 90 consecutive baking cycles were performed on each coated specimen. In a second test, the coatings were abraded by sanding, followed by 30 baking cycles. In both cases, take-off pressure was evaluated to extract the pancake model, as well as water sliding angle, surface roughness and surface damage. The results have shown that perfluoroalkoxyalkane (PFA) and polytetrafluoroethylene (PTFE) were the most effective in terms of pull-off pressure (<3 kPa) versus ceramic siloxane coatings with values between 15 and 34 kPa after 90 firings. In the different experimental stages, a positive correlation between wettability and detachment force was observed, especially for fluoropolymer coatings. However, surface roughness did not strong correlate with the pull-off force, low values did not correlate with low values of pull-off force and vice versa. This paper proposes an objective and simple coating evaluation procedure for industrial environments. Although ceramic sol-gel coatings show potential, there is a need to improve their non-stick capability to bring them on par with traditional solutions.