Method and apparatus for measuring corrosion beneath thin films

摘要

A method and an apparatus are provided which can quantitatively measure the corrosion-inhibiting ability of thin films of materials such as lubricants. A galvanic cell is created on a sensitive surface using alternating layers of anodic and cathodic materials such as steel and copper, which are electrically isolated by an insulation matrix. The surface is then coated with a film of the material to be tested which is then allowed to drain therefrom. The surface is then cooled to below the dew point of the surrounding environment to cause condensation on the thin film. The galvanic current between the anodic and cathodic materials is then monitored for the first indication of environmental penetration through the film, i.e., corrosion.