Method and apparatus for measuring corrosion beneath thin films
First Claim
1. Apparatus for monitoring the corrosion beneath a thin film of lubricant exposed to a humid environment having a known dew point temperature comprising:
- a matrix of insulating material having an essentially flat sensitive bevelled face oriented at an angle with the horizontal ranging from 10 to 80 degrees, on which the thin film of lubricant is to be disposed;
a plurality of electrically isolated surface areas of anodic material disposed on the sensitive face;
a plurality of electrically isolated surface areas of cathodic material disposed on the sensitive face in alternating relationship with the anodic surface areas;
a first conducting means connected to each of the anodic surface areas;
a second conducting means connected to each of the cathodic surface areas; and
means electrically connected to said first and said second conducting means for measuring the current generated therebetween, the current being the corrosion current generated at the sensitive face beneath the thin film of lubricant.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and an apparatus are provided which can quantitatively measure theorrosion-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.
18 Citations
25 Claims
-
1. Apparatus for monitoring the corrosion beneath a thin film of lubricant exposed to a humid environment having a known dew point temperature comprising:
-
a matrix of insulating material having an essentially flat sensitive bevelled face oriented at an angle with the horizontal ranging from 10 to 80 degrees, on which the thin film of lubricant is to be disposed; a plurality of electrically isolated surface areas of anodic material disposed on the sensitive face; a plurality of electrically isolated surface areas of cathodic material disposed on the sensitive face in alternating relationship with the anodic surface areas; a first conducting means connected to each of the anodic surface areas; a second conducting means connected to each of the cathodic surface areas; and means electrically connected to said first and said second conducting means for measuring the current generated therebetween, the current being the corrosion current generated at the sensitive face beneath the thin film of lubricant. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. Apparatus for monitoring the corrosion beneath a thin film of lubricant exposed to a humid environment having a known dew point temperature, comprising:
-
a matrix of insulating material having a substantially horizontal face and an essentially flat sensitive face adjacent thereto and forming an angle therewith ranging from 10 to 80 degrees, on which the thin film of lubricant is to be disposed; a plurality of plates of an anodic material embedded within said matrix and positioned such that each of said anodic plates is surrounded by said matrix with one edge forming part of the sensitive face; a plurality of plates of a cathodic material embedded within said matrix in alternating relationship with the anodic plates and positioned such that each of said cathodic plates is surrounded by said matrix with one edge forming part of the sensitive face; means operatively connected to the sensitive face for cooling the face to a temperature below the dew point temperature such that condensation forms on the thin film of lubricant; a first conducting means connected to each of said anodic plates; a second conducting means connected to each of said cathodic plates; and means electrically connected to said first and said second conducting means for measuring the current generated therebetween, the current being the corrosion current generated at the sensitive face beneath the thin film of lubricant. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
23. A method for monitoring the corrosion beneath a thin film of lubricant comprising the steps of:
-
providing an essentially flat sensitive bevelled face oriented at an angle with the horizontal ranging from 10 to 80 degrees and having disposed thereon a plurality of electrically isolated anodic and cathodic surface areas in an alternating relationship; coating the sensitive face with the thin film of lubricant and allowing the lubricant to drain therefrom; exposing the coated face to a humid environment having a known dew point temperature; cooling the coated face to a temperature below the dew point temperature, causing condensation to form on the thin film of lubricant; and measuring the current generated between the anodic and cathodic surface areas, the current being the corrosion current generated at the sensitive face beneath the thin film of lubricant. - View Dependent Claims (24, 25)
-
Specification