Parylene provides highly effective corrosion protection by acting as a dense, conformal barrier against moisture, dissolved salts, and a broad range of aggressive chemical agents. Its low water vapor permeability and chemically inert molecular structure significantly reduce the diffusion of corrosive species to underlying metallic substrates [1]. Typical film thicknesses between 10–25 µm provide robust environmental protection while adding negligible mass. Unlike many acrylic or polyurethane conformal coatings, Parylene does not swell or soften in prolonged contact with hydrocarbons, maintaining adhesion and dimensional stability.
The coating demonstrates strong resistance in demanding environments, including salt spray exposure in accordance with IEC 60068-2-52 [2], hydrocarbons and common organic solvents, dilute acidic and alkaline solutions and phosphate-ester-based aerospace hydraulic fluid.
[1] L. Li, J. H. Kim, and T. I. Kamins, “Barrier properties and corrosion protection of Parylene coatings,” Surface and Coatings Technology, vol. 200, pp. 425–429, 2005.
[2] IEC 60068-2-52, Environmental testing – Part 2-52: Tests – Test Kb: Salt mist, cyclic (sodium chloride solution), International Electrotechnical Commission
